Composite material and method of preparing the same from substantially unsorted waste

ABSTRACT

A composite material having thermoplastic properties and comprising organic matter and optionally one or both of inorganic matter and plastic with unique characteristics is provided. Such a composite material may be prepared from waste such as domestic waste. For preparation of the composite material, waste is dried, optionally particulated. The dried and optionally particulated waste material is then heated, while mixing under shear forces. The composite material is processed to obtain useful articles.

This application is a divisional of U.S. patent application Ser. No.13/144,495, filed Jul. 14, 2011, which is a national phase filing under35 U.S.C. 371 of PCT International Application No. PCT/IL2010/000042,filed Jan. 17, 2010, which claims priority benefit of U.S. ProvisionalApplication No. 61/193,985, filed Jan. 15, 2009, the entirety of whichare hereby incorporated herein by reference.

FIELD OF THE INVENTION

The invention disclosed herein relates to waste treatment, particularly,domestic or municipal waste and more particularly to methods fortransforming substantially unsorted waste into useful products as wellas such products.

BACKGROUND OF THE INVENTION

There is a growing awareness and recognition of the importance ofrecycling, nevertheless, only a fraction of the generated municipalwaste is actually recycled. It has been reported by the United StatesEnvironmental Protection Agency that in 2007, Americans generated 254million tons of municipal waste. Of this only 63 million tons wasrecycled, 22 million tons composted, and 32 million tons was combustedto produce energy. That means that 137 million tons were simplydiscarded, mostly to landfills.

Economics is the primary reason for the limited amount of waste that isrecycled. Simply speaking, if recycling does not generate a profit it isnot done. The significant costs involved in recycling are sorting,transportation and the energy used in the sorting and transportationprocesses.

Various technologies have been developed over the years aimed atproviding low cost useful products from municipal wastes.

U.S. Pat. No. 3,850,771 provides a process for processing waste whereina portion of cellulose from the waste is separated (sorted) from thebulk of the waste and transformed into cellulose xanthate. The cellulosexanthate, being soluble, is uniformly distributed back into the wasteand upon conversion back to the cellulose form, it binds the wastecomponents. It is taught that the cellulose in the waste is essentiallyuseless and may in fact be objectionable. These are the reasons that thepatent teaches to remove a portion from the waste, convert it, and thenremix it with the waste, and upon further treatment, the celluloseprecipitates to form a binder.

U.S. Pat. No. 4,013,616 describes a method of using comminuted municipalor industrial waste as a filler for thermosetting or thermoplasticresins such as polyethylene and using the filled resin to make a usefulproduct. The process requires a presorting of the waste into light andheavy fractions. Moreover, the patent teaches that the plastics in theoriginal waste are not suitable as binding agents. The components makingup a typical municipal waste are set forth in Table 1 of the patent.

U.S. Pat. No. 4,772,430 describes a process for compacting solid wastecontaining at least 10% by weight thermoplastic materials using anextrusion molder to obtain high-density rod-like masses or pellets. Therod-like masses or pellets consist of non-homogenous aggregates ofmiscellaneous waste materials and because of the process conditions, theplastic is concentrated at the peripheral portion of the composite toform a plastic solidified layer, like a crust.

U.S. Pat. No. 4,968,463 describes a method focusing on disposing ofplastic waste wherein it is important that the thermoplastic content beover 65% by weight and the water content be less than 3% whereinoptionally adding filler (which can also be a waste) and coloringmaterials. The product is characterized by having a bending rupturestress (flexural strength) of 35-50 N/mm² and is processable withmachine tools used for wood.

U.S. Pat. No. 5,217,655 describes a composite product obtained by firstgranulating a mixture of plastic and fibrous material, e.g. acommercial, municipal or industrial waste from which, preferably, metalhas been removed, and then heating the mixture in stages from about100-204° C. while continuously mixing in an extruder. The compositematerial may contain at least 50% thermoplastic material and isdescribed as having high impact properties, high compression strength,may be coated with coloring agents and may be used for industrial posts,beams and construction columns.

U.S. Pat. No. 6,017,475 describes a process utilizing a hydrolyzer forthe complete hydrolysis of ligno-cellulose matter in waste. The processyields sterile cellulose pulp aggregates having traces of metals,plastics etc., macroscopically mixed in the aggregates. The aggregatesare separable into pure cellulose pulp and a residual mixture containinginorganic pulp. The cellulose pulp and/or the residue may be furtherextruded, optionally with plastics or other additives to form usefulproducts. Some products of the process are described in WO 2005/092708and US2004/0080072.

U.S. Pat. No. 6,253,527 describes a method of compression molding ofwaste or filler particles that are bound together and encapsulated by athermoplastic binder. The composite material is prepared by mixingparticles of thermoplastic and waste or fillers; using high intensitymixing to frictionally heat the particles bringing the thermoplasticparticles to a molten state where they coat and encapsulate the waste orfiller particles. The molten mass is then compression molded.

U.S. Pat. No. 6,423,254 describes a method for manufacturing productsfrom various types of waste materials comprising about 80% polyolefinsand about 20% other thermoplastic polymers. The waste may be used incombination with raw materials such as wood, plastics, metals,heat-stabilizers and blowing agents.

KR 2003/0014929 describes a composite material obtained from waste fromwhich metal was sorted out. The composite material comprises between30-70% thermoplastic materials after sorting out metals, inter alia,because the metals cause problems in the grinding process.

WO 2006/079842 describes a method for processing clinical wastecontaining between 10% and 50% thermoplastic material, about 20% water,and the rest consisting of mainly cotton, adhesives, rubber and metal.The product is moldable and has a density of 200-500 Kg/m³.

WO2006/035441 describes a method of encapsulating pieces of waste withmelted plastic by heating and mixing.

SUMMARY OF THE INVENTION

The present invention is based on the surprising finding that subjectingsubstantially unsorted waste to shear forces at temperatures above 100°C. resulted in a composite material having thermoplastic properties.

Thus, the present invention provides a composite material havingthermoplastic properties and comprising organic matter and optionallyone or both of inorganic matter and plastic, having a surface energyabove about 35 dyne/cm.

The present invention also provides a composite material havingthermoplastic properties and comprising organic matter and optionallyone or both of inorganic matter and plastic, having essentially no gapsbetween different components of the material when viewed at amagnification revealing structures above about 0.1 μm. Thus, inaccordance with this embodiment particulate matter (e.g. small inorganicparticles, fibers, solids particles of different origin etc.) are veryclosely associated with the surrounding medium such that gaps, if any,are of a size (width) of less than 0.1 μm. While not wishing to be boundby theory, this is believed to be a result of the adhesive properties ofthe new composite material that is comprised in said surrounding medium.

Also provided by the invention is a composite material havingthermoplastic properties and comprising organic matter and optionallyone or both of inorganic matter and plastic, said composite material hasa phase transition from a solid to a flowable state at a temperatureless than about 120° C., at times even less than about 110° C., lessthan about 100° C. and even at a temperature as low as about 90° C.

Also provided by the invention is a composite material havingthermoplastic properties and comprising organic matter and optionallyone or both of inorganic matter and plastic, characterized by one ormore of the following:

-   -   having a phase transition from a solid to a flowable state at a        temperature less than about 120° C., at times even less than        about 110° C., less than 100° C. and even at a temperature as        low as 90° C.,    -   having essentially no gaps between different components of the        material when viewed at a magnification revealing structures        above about 0.1 μm,    -   having a surface energy above about 35 dyne/cm    -   having a density above about 1.2 g/cm³,    -   having a potassium content above about 1 mg potassium per 1 gm        of composite material (mg/g),    -   having tensile strength of above about 4 MPa,    -   having tensile modulus of above about 600 MPa,    -   having flexural modulus above about 800 or even 1000 MPa,    -   having flexural strength above about 7 MPa,    -   having a notched Izod impact above about 12 J/m,    -   having a Charpy impact of above about 1.5 KJ/m², 1.6 KJ/m², 1.7        KJ/m², or 1.8 KJ/m²,    -   releasing volatile compounds comprising one or more of butanone,        acetic acid, butanoic acid, furfural, and phenol (these        components induce a characteristic odor; the odor can be        eliminated by the addition of odor absorbents); other volatiles,        e.g. such typically released organic or non-organic waste may        also be released from the composite material,    -   comprising DNA,    -   comprising chlorophyll.

In the following all indication of % relate to the relative amounts ofcomponents in w/w units, namely weight of a component in 100 units ofweight of the composite material. The relative amount may be determinedin the final product or may be determined in the starting material(s),used to produce the composite material, before processing (typically byheating under shear forces) or in samples taken during processing beforeobtaining the resulting final, composite material. As will beappreciated there may be some (typically small) variation between therelative amount of a component in the starting material before it isprocessed and the obtained composite material due to a loss of moisture,the formation of some volatile compounds during processing and otherfactors that should be taken into account when comparing the content ofa component in the composite material and that in the starting material.

All amounts or measures indicated below with the term “about” followedby a number should be understood as signifying the indicated number witha possible tolerance between approximately 10% above the indicatednumber and 10% below that number. For example, the term “about 10%”should be understood as encompassing the range of 9% to 11%; the termsabout 100° C. denotes a range of 90 to 110° C.

The composite material of the invention may comprise plastic in therange of between about 0 and about 40%, typically, however not exceedingabout 35% or even about 30% of the composite material. The amount ofplastic in some embodiments may be at least n %, n being any integer inthe range of 1 to 20; in some embodiments the plastic material may be inan amount less than m %, m being an integer in the range of 15 to 29.

The composite material in some embodiments may comprise at least about10% organic matter (other than synthetic polymeric material), typicallyat least about 15%, about 20%, about 25%, about 30%, about 35% or evenabout 40%; in some embodiments the composite material may comprise up toabout 90%, typically less than about 85%, about 80%, about 75% or evenless than about 70% of organic matter.

According to some embodiments the composite material comprises at leastabout 1%, about 2%, about 5%, about 10% or at least about 15% ofinorganic matter; by some embodiments the composite material comprisesless than about 50%, about 40%, about 30% or even less than about 20% ofinorganic matter.

By some embodiments the composite material is prepared by extrusion.

By some embodiments the composite material is injection molded.

By some embodiments the composite material is prepared by rotationalmolding.

By some embodiments the composite material is compression molded.

By some embodiments the composite material is formed into granules.

The different preparation methods may be used to advantage for preparingcomposite materials of the invention with properties to suit specificneeds or may be used for forming the composite material into differentuseful articles.

For further processing and production of articles said compositematerial in the form of granules or any other form may be mixed withother materials such as recycled or virgin plastics and then molded intouseful articles. The plastic materials are typically polyolefins such aspolyethylene or polypropylene, polyvinylchloride, unsorted plastic wasteor mixtures thereof. In some embodiments said composite material may bemixed with a variety of different substances or materials non-limitingexamples being minerals (e.g. calcium carbonate), salts, metal particlesor pieces, organic or inorganic fibers, glass, carbon (e.g. activecarbon), sand, ground rock, clay, gravel, and many others.

By some embodiments of the invention the composite material is preparedfrom unsorted or substantially unsorted waste (defined below), forexample municipal, industrial or other waste. At times the waste may beused as is, as the raw material for preparing the composite material (byheating under shear forces). Also the waste may at times be subject toremoval of some components, for example, metal or other inorganicmaterial, to avoid abrasion by such components of the processingequipment, for example an extruder.

The present invention also provides a method of processing wastematerial. This method comprises: drying and optionally particulatingsubstantially unsorted waste that comprises organic matter andoptionally plastics to obtain dried and optionally particulate wastematerial; and heating while mixing the dry particulate waste material toa temperature of at least about 100° C., under shear forces. Thereby acomposite material with thermoplastic properties is obtained.

The extent of the shear forces may influence the properties of thecomposite material. Shear forces may occur by mixing an industrial mixeror agitator, may occur within an extruder, and in many other instrumentsor machinery.

Said composite material may be used to prepare articles having a definedshape. The articles may be prepared by processing the composite materialor a mixture comprising the composite material and other materials suchas plastic or others exemplified below, at temperatures in the range ofabout 100° C. and about 240° C., or in the range of about 140 and about230° C., or even in the range of about 180 to about 220° C., to assumethe desired shape. Said composite material may optionally beparticulated and sieved before heating. The articles may be obtained byextrusion of the composite material or the mixture comprising thecomposite material, followed by molding (injection molding, compressionmolding, rotational molding etc.) Thus, also forming part of the presentinvention are articles formed from the composite material havingthermoplastic properties disclosed herein.

Accordingly, the invention also provides a method for preparing articlesmade from the composite material of this invention comprising, obtainingthe composite material as described above, optionally grinding thecomposite material, optionally sieving the composite material,optionally mixing the composite material with other materials such asplastics and sand, heating and mixing the composite material or themixture comprising the composite material under shear forces and moldingthe same into an article having a desired shape.

Finally, there is provided by the present invention a method forcompacting waste, comprising: drying and optionally particulatingsubstantially unsorted waste that comprises organic matter andoptionally plastics to obtain dried and optionally particulate wastematerial; heating while mixing the dried waste material to a temperaturein the range of about 100° C. and about 240° C., or in the range ofabout 140 and about 230° C., or even in the range of about 180 to about220° C. under shear forces to obtain a resulting composite material; andforming the resulting composite material into blocks or other articlesof a defined shape.

Embodiments

Some non-limiting embodiments encompassed by the present invention aredefined in the following numbered clauses:

1. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic, characterized by one or more of the following:

-   -   having a phase transition from a solid to a flowable state at a        temperature less than about 120° C.,    -   having no gaps between different components of the material when        viewed at a magnification revealing structures above 0.1 μm,    -   having a surface energy above about 35 dyne/cm,    -   having a density above about 1.2 g/cm³,    -   having a potassium content above about 1 mg potassium per 1 gm        of composite material (mg/g),    -   having tensile strength of above about 4 MPa,    -   having tensile modulus of above about 600 MPa,    -   having flexural modulus above about 800 MPa,    -   having flexural strength above about 7 MPa,    -   having a notched Izod impact above about 12 J/m,    -   having a Charpy impact of above about 1.5 KJ/m², 1.6 KJ/m², 1.7        KJ/m², or 1.8 KJ/m²,    -   releasing volatile compounds comprising one or more of butanone,        acetic acid, butanoic acid, furfural, and phenol,    -   comprising DNA,    -   comprising chlorophyll.

2. The composite material of clause 1, comprising plastic material inthe range of about 0-30%, organic material in the range of about 10-70%,and inorganic material in the range of about 0-70.

3. The composite material of numbered clause 1 or 2, comprising up to40% plastic.

4. The composite material of numbered clause 3, comprising up to 35%plastic.

5. The composite material of numbered clause 4, comprising up to 30%plastic.

6. The composite material of any one of the previous numbered clauses,comprising plastic in the range of n % and m %, wherein n is any integerbetween 1 and 18 and m is any integer between 19 and 29.

7. The composite material of any one of the preceding numbered clauses,comprising organic material in the range of about 10% to about 90%.

8. The composite material of clause 7, comprising at least about 15% oforganic matter.

9. The composite material of clause 8, comprising at least about 20% oforganic matter.

10. The composite material of clause 9, comprising at least about 25% oforganic matter.

11. The composite material of clause 10, comprising at least about 30%of organic matter.

12. The composite material of clause 11, comprising at least about 35%of organic matter.

13. The composite material of clause 12, comprising at least about 40%of organic matter.

14. The composite material of any one of clauses 7 to 13, comprisingless than about 85% of organic matter.

15. The composite material of clause 14, comprising less than about 80%of organic matter.

16. The composite material of clause 15, comprising less than about 75%of organic matter.

17. The composite material of clause 16, comprising less than about 70%of organic matter.

18. The composite material of any one of the preceding numbered clauses,comprising inorganic matter in the range of 0% to about 50%.

19. The composite material of clause 18, comprising about 1% or more ofinorganic matter.

20. The composite material of clause 19, comprising about 2% or more ofinorganic matter.

21. The composite material of clause 20, comprising about 5% or more ofinorganic matter.

22. The composite material of clause 21, comprising about 10% or more ofinorganic matter.

23. The composite material of clause 22, comprising about 15% or more ofinorganic matter.

24. The composite material of any of clauses 18-23, comprising less thanabout 50% of inorganic matter.

25. The composite material of clause 24, comprising less than about 40%of inorganic matter.

26. The composite material of clause 25, comprising less than about 30%of inorganic matter.

27. The composite material of clause 26, comprising less than about 20%of inorganic matter.

28. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic and having a phase transition from a solid to a flowable stateat a temperature of less than about 120° C.

29. The composite material of clause 28, wherein the phase transition isat a temperature of less than about 110° C.

30. The composite material of clause 29, wherein the phase transition isat a temperature of less than about 100° C.

31. The composite material of clause 30, wherein the phase transition isat a temperature in the range of about 90 to about 100° C.

32. The composite material of any one of clauses 28 to 31, having one ormore of the features defined in clauses 1-26.

33. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic and having essentially no gaps between different components ofthe material when viewed at a magnification revealing structures aboveabout 0.1 μm.

34. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic and comprising particles embedded in a matrix, the matrix beingintimately associated with external surfaces of the particlesessentially without gaps therebetween when viewed at a magnificationrevealing structures above 0.1 rim.

35. The composite material of clause 33 or 34, having one or more of thefeatures defined in any one of clauses 1-32.

36. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic and having a surface energy above about 35 dyne/cm.

37. The composite material of clause 36, having a surface energy aboveabout 40 dyne/cm.

38. The composite material of clause 36 or 37, having one or more of thefeatures defined in any one of clauses 1-31.

39. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic and having a density above about 1.2 g/cm³.

40. The composite material of clause 39, having a density in the rangeof about 1.2 and 1.7 g/cm³.

41. The composite material of clause 39 or 40, having one or more of thefeatures defined in any one of clauses 1-37.

42. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic and having a potassium content above about 1 mg/g.

43. The composite material of clause 42, having one or more of thefeatures defined in any one of clauses 1-40.

44. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic and having tensile strength of above about 4 MPa.

45. The composite material of clause 44, having tensile strength ofabove about 5 MPa.

46. The composite material of clause 45, having tensile strength ofabove about 6 MPa.

47. The composite material of clause 46, having tensile strength ofabove about 7 MPa.

48. The composite material of clause 47, having tensile strength ofabove about 8 MPa.

49. The composite material of any one of numbered clauses 44 to 48,having one or more of the features defined in any one of clauses 1-42.

50. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic and having tensile modulus of elasticity above about 600 MPa.

51. The composite material of clause 50, having one or more of thefeatures defined in any one of clauses 1-48.

52. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic and having flexural modulus above about 800 MPa.

53. The composite material of clause 52, wherein the flexural modulus isabove about 1000 MPa.

54. The composite material of clause 53, wherein the flexural modulus isabove about 2000 MPa.

55. The composite material of clause 54, wherein the flexural modulus isabove about 3000 MPa.

56. The composite material of clause 55, wherein the flexural modulus isabove about 3500 MPa.

57. The composite material of any one of numbered clauses 52 to 56,having one or more of the features defined in any one of clauses 1-50.

58. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic and having flexural strength above about 7 MPa.

59. The composite material of clause 58, wherein the flexural strengthis above about 9 MPa.

60. The composite material of clause 59, wherein the flexural strengthis above about 11 MPa.

61. The composite material of any one of numbered clauses 58 to 60,having one or more of the features defined in any one of clauses 1-56.

62. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic and having a notched Izod impact above about 12 J/m.

63. The composite material of clause 62, wherein the notched Izod impactis above about 13 J/m.

64. The composite material of clause 63, wherein the notched Izod impactis above about 15 J/m.

65. The composite material of clause 64, wherein the notched Izod impactis above about 17 J/m.

66. The composite material of any one of numbered clauses 62 to 65,having one or more of the features defined in any one of clauses 1-60.

67. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic and having a Charpy impact of above about 1.5 KJ/m².

68. The composite material of clause 67, wherein the Charpy impact isabove about 1.6 KJ/m².

69. The composite material of clause 68, wherein the Charpy impact isabove about 1.7 KJ/m²

70. The composite material of clause 69, wherein the Charpy impact isabove about 1.8 KJ/m².

71. The composite material of any one of numbered clauses 67 to 70,having one or more of the features defined in any one of clauses 1-65.

72. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic and releasing volatile compounds comprising one or more ofbutanone, acetic acid, butanoic acid, furfural, and phenol.

73. A composite material having thermoplastic properties and comprisingorganic matter and optionally one or both of inorganic matter andplastic and comprising DNA.

74. The composite material of clause 72 or 73, having one or more of thefeatures defined in any one of numbered clauses 1-70.

75. The composite material of any one of the preceding numbered clauses,prepared by extrusion.

76. The composite material of any one of the preceding numbered clauses,being compression or injection molded.

77. The composite material of any one of the preceding numbered clauses,prepared from substantially unsorted waste.

78. The composite material of clause 77, prepared from substantiallyunsorted waste which is devoid of some inorganic material included inunsorted waste.

79. The composite material of clause 78, prepared from substantiallyunsorted waste which is devoid of some metal included in unsorted waste.

80. A method of processing waste material, comprising:

-   -   drying and optionally particulating substantially unsorted waste        that comprises organic matter and optionally plastics to obtain        dried and optionally particulate waste material; and heating        while mixing the dry particulate waste material to a temperature        of at least about 100° C. under shear forces to thereby obtain a        composite material with thermoplastic properties.

80A. A method for preparing a composite material, comprising:

-   -   obtaining a mixture comprising organic matter and optionally        plastics; and    -   heating the mixture to a temperature of at least about 100° C.        under shear forces to thereby obtain a composite material with        thermoplastic properties

81. The method of clause 80 or 80A, further comprising particulatingsaid composite material.

82. The method of clause 80-81, wherein the temperature is at least 120°C.

83. The method of clause 82, wherein the temperature is at least 140° C.

84. The method of clause 83, wherein the temperature is at least 160° C.

85. The method of clause 84, wherein the temperature is in the range of180° C. to 220° C.

86. The method of any one of clauses 80-85, for manufacture of acomposite material as defined in any one of the numbered clauses 1-79.

87. Articles formed from the composite material as defined in any one ofclauses 1-79 or a composite material prepared in a manner as defined inclauses 80-86.

88. A method for manufacturing an article comprising:

-   -   drying and optionally particulating substantially unsorted waste        that comprises organic matter and optionally plastics to obtain        dried and optionally particulate waste material;    -   heating while mixing the dried waste material to a temperature        in the range of about 100° C. and about 240° C. under shear        forces to obtain a composite material;    -   molding the composite material to form the article.

89. A method for compacting waste, comprising:

-   -   drying and optionally particulating substantially unsorted waste        that comprises organic matter and optionally plastics to obtain        dried and optionally particulate waste material;    -   heating while mixing the dried waste material to a temperature        in the range of about 100° C. and about 240° C. under shear        forces to obtain a composite material; and    -   forming the resulting composite material into blocks or other        articles of a defined shape.

90. The method of clauses 88 or 89, wherein the temperature is in therange of about 140 and about 230° C.

91. The method of clause 90, wherein the temperature is in the range ofabout 180 and about 220° C.

92. The method of any one of clauses 80-91, wherein the heating undershear forces is carried out in an extruder.

93. The method of any one of clauses 80-92, wherein the substantiallyunsorted waste is particulated.

94. The method of clause 93, wherein the particulating is carried out bya granulator.

95. A method for manufacturing an article comprising heating thecomposite material of any one of clauses 1-79 to cause said material toflow and forming it to a desired shape to obtain said article.

96. The method of clause 95, wherein the heating is to a temperature inthe range of 100° C. and 240° C.

97. The method of any one of clauses 88-95, wherein the compositematerial is continuously formed and molded to a desired shape.

98. A method for preparing a composite material having one or more ofthe following properties at solid state: having a phase transition froma solid to a flowable state at a temperature less than about 120° C.;having no gaps between different components of the material when viewedat a magnification revealing structures above 0.1 μm; having a surfaceenergy above about 35 dyne/cm; having a density above about 1.2 g/cm³;having a potassium content above about 1 mg/g (mg potassium per 1 gm ofcomposite material); having tensile strength of above about 4 MPa,having tensile modulus of above about 600 MPa; having flexural modulusabove about 800 MPa; having flexural strength above about 7 MPa; havinga notched Izod impact above about 12 J/m; having a Charpy impact ofabove about 1.5 KJ/m², 1.6 KJ/m², 1.7 KJ/m², or 1.8 KJ/m²; releasingvolatile compounds comprising one or more of butanone, acetic acid,butanoic acid, furfural, and phenol; comprising DNA; and comprisingchlorophyll;

-   -   the method comprising:    -   drying and particulating substantially unsorted waste that        comprises organic material and plastics to obtain dried waste        material and heating while mixing the dried particulate material        under shear forces to a temperature of at least about 100° C.        thereby obtaining a processed composite material.

99. The method of clause 98, wherein the temperature is at least 120° C.

100. The method of clause 99, wherein the temperature is at least 140°C.

101. The method of clause 100, wherein the temperature is at least 160°C.

102. The method of clause 101, wherein the temperature is in the rangeof 180° C. to 220° C.

103. A method for processing waste comprising:

-   -   drying and optionally particulating substantially unsorted waste        that comprises organic matter and optionally plastics to obtain        dried and optionally particulate waste material;    -   heating while mixing the dried waste material to a temperature        in the range of about 100° C. and about 240° C. under shear        forces to obtain a composite material; and    -   particulating the composite material.

104. The method of any of clauses 88-97, wherein the composite materialis particulated after formation and the particulated composite materialis then molder into said article.

105. The method of clause 104 wherein the composite material is grindedand the grinded composite material is reheated and mixed under shearforces before it is molded to obtain the article.

106. The method of any one of clauses 104 or 105, wherein the grindedcomposite material is reheated and mixed with another material undershear forces before it is molded to obtained the article.

107. An article comprising two or more materials adhered to or blendedwith one another, wherein at least one of said materials is thecomposite material of any one of clauses 1-79 or a composite materialobtained by any one of the methods of clauses 80-94 and 104-106.

108. The article of clause 107 wherein the two or more materials areessentially homogenously blended with one another.

109. The article of clause 107 or 108, wherein said blend comprisespolyethylene, polyvinylchloride, polypropylene, unsorted plastic wasteor a mixture thereof.

110. The article of clause 108 or 109 comprising a first material and asecond material adhered to one another, wherein at least one of thefirst or second material is a composite material as defined in any ofclause 1-79.

111. A pallet for storage or fork-lifting made of a blend comprising acomposite material as defined in any of clauses 1-79.

112. The pallet of clause 111 prepared by injection molding of saidblend.

113. The pallet of clause 111 or 112, wherein said blend comprises saidcomposite material and high density polyethylene.

114. A storage article made of a blend comprising a composite materialas defined in any of clauses 1-79.

115. The article of clause 114, being a tool box.

116. The article of clause 114 or 115, prepared by injection molding.

117. The article of any one of clauses 114-116, wherein said blendcomprises polyethylene, polyvinylchloride, polypropylene, unsortedplastic waste or a mixture thereof.

118. A weight-holding panel made of blend comprising a compositematerial according to any one of clauses 1-79.

119. The panel of clause 118, being usable as shelf.

120. The panel of clause 118 or 119 prepare by injection molding.

121. The panel of any one of clause 118-120, where said blend compriseshomo polypropylene and calcium carbonate.

122. An article made of a blend comprising the composite material of anyof clauses 1-79, a polypropylene copolymer and carbon black,

123. An article made of a blend comprising the composite material of anyof clauses 1-79, prepared by molding.

124. An article made of a blend comprising the composite material of anyof clauses 1-79, prepared by injection molding.

125. An article made of a blend comprising the composite material of anyof clauses 1-79, prepared by rotational molding.

126. An article made of a blend comprising the composite material of anyof clauses 1-79, prepared by compression molding.

127. The article of any one of clauses 122-126, wherein the blendcomprises a plastic material.

128. The article of clause 127 wherein the plastic is polyethylene,polyvinylchloride, polypropylene, unsorted plastic waste or a mixturethereof.128.

The article of any one of clauses 107-127, wherein paint is applied onat least visible surfaces of the article.

129. Use of substantially unsorted waste for the production of articlesas defined in anyone of clauses 122 to 128.

130. A method for preparing articles, comprising:

-   -   providing the composite material of any one of clause 1-79 or        preparing a composite material in a manner as defined in any of        clause 80-102;    -   optionally processing the composite material by one or both        of (i) grinding the composite material, and (ii) sieving the        composite material;    -   heating and mixing the composite material under shear forces to        obtain a melt; and    -   shaping the melt into an article.

131. The method of clause 130, comprising mixing the composite materialbefore, during or after the heating and mixing with one or more othermaterials, whereby said melt is a mixture of said composite material andthe one or more other materials.

132. The method of clause 130, comprising adding other materials to saidcomposite material during heating and mixing.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to understand the invention and to see how it may be carriedout in practice, embodiments will now be described, by way of anon-limiting example only, with reference to the accompanying drawings,in which:

FIG. 1 is a flow chart of analysis by extraction in organic solvents ofa composite material according to an embodiment of the invention;

FIG. 2 is a DNA gel electrophoresis performed on extracts from threespecimens: compression molding of an extrudate according to theinvention (lane (1)); positive control (lane 2); negative control (lane3); and dried and particulated substantially unsorted waste (SUW) (lane(4)); MM represents DNA molecular marker reference;

FIG. 3 is a thermogravimetric analysis (TGA) of a composite materialaccording to an embodiment of the invention showing its % loss of weightas a function of temperature increase;

FIG. 4 is a graph showing the derivative of weight loss versustemperature from the thermogravimetric analysis shown in FIG. 3;

FIG. 5 shows the storage modulus of a thermoplastic composite materialof an embodiment of the invention prepared by two methods: injectionmolding (continuous line), and compression molding (dashed line)according to the invention, determined by dynamic mechanical thermalanalysis (DMTA);

FIG. 6 shows the loss modulus of a composite material according to theinvention prepared by injection molding (continuous line) compared to acompression molding (dashed line) as determined by DMTA;

FIG. 7 shows the room temperature notched Izod impact energy as functionof injection molding temperature ranging from about 160° C. to about220° C., of a composite material according to an embodiment of theinvention;

FIG. 8 is a graph showing the Capillary Rheometer viscosity of acomposite material according to an embodiment of the invention, as afunction of shear rate, tested at various temperatures;

FIGS. 9A and 9B provide Brabender plastograph test results of (i) acomposite material according to an embodiment of the invention (FIG. 9Aat 200° C.) and (ii) polypropylene (PP) used as a reference (9B at 240°C.), using a rotor speed of 80 rpm.;

FIGS. 10A-10C are light microscope reflection micrographs at differentmagnifications (×50, FIG. 10A; ×100, FIG. 10B; and ×200, FIG. 10C) ofthe external surface of a solid composite material according to anembodiment of the invention;

FIGS. 11A-11B are scanning electron micrographs (SEM) of cryogenicfracture surfaces of a composite material according to an embodiment ofthe invention;

FIGS. 12A-12D are chromatograms of head space gas chromatography massspectroscopy (HS-GCMS) of solid phase micro-extraction of a compositematerial according to an embodiment of the invention (FIG. 12A);unsorted organic waste (FIG. 12B); unsorted plastic waste (FIG. 12C) andpolypropylene (FIG. 12D);

FIGS. 13A-13E are photographs of several examples of articles preparedfrom a composite material according to some examples described below,wherein FIG. 13A shows a pallet prepared by injection molding, FIG. 13Bshows a composter bottom part prepared by injection molding, FIG. 13Cshows a sewer opening cover prepared by injection molding, FIG. 13Dshows flower pots prepared by cold compression molding and subsequentlypainting of the composite material (the different grey shadingsrepresent different colors), and FIG. 13E shows a tubular body preparedby extrusion;

FIG. 14 is a schematic illustration of a system for treating SUW inaccordance with one embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is based on the surprising finding that subjectingsubstantially unsorted waste (SUW) to shear forces at temperatures above100° C. resulted in a composite material having thermoplasticproperties. The SUW is substantially unsorted municipal solid waste.

Municipal solid waste (MSW) as used herein refers to residential andcommercial trash (garbage), that is discarded by people and industry andis typically composed of primarily, wood, wood derived products such aspaper, cardboard, tissues and the like, food scraps and plastics. In2007 the Environmental Protection Agency reported in the United Statesthat MSW was composed of the following ingredients, as percent byweight: Paper (32.7%), Glass (5.3%), Metals (8.2%), Plastics (12.1%),Rubber, leather and textiles (7.6%), Wood (5.6%), Yard Trimmings(12.8%), Food Scraps 12.5%), Other (3.2%). Israel reported a similaranalysis for 2005: Organic matter (40%), Plastic (13%, predominatelythermoplastics), Cardboard (8%), Paper (17%), Textiles (4%) Disposablediapers (5%), Other (7%), Glass (3%) and Metals (3%). These percentagesare averages and actual percentages will vary from location to location,but it is clear that the predominant components in these wastes areplastics and cellulosic type materials, e.g. wood and components derivedfrom wood, e.g. paper, tissues, paperboard, etc. The MSW usually containmoisture.

The thermoplastic component in the waste includes, for example,polyolefins, polystyrene, polyvinylchloride, polyethylene terephthalate,polyacrylonitrile, polybutadiene, polystyrene, polycarbonate, nylon, andthe like. Thermosets make up a very small portion of the normal MSW butcan be part of the waste stream.

The composite material disclosed herein has unique thermoplasticproperties. The term “thermoplastic properties”, as used herein, refersto a property where a solid or essentially solid material turns uponheating into a hot flowable material (soft, malleable, moldable,remoldable and, extrudable, weldable material) and reversibly solidifieswhen sufficiently cooled. The term also denotes that the material has atemperature or a temperature range at which it becomes a hot flowablematerial. This property is similar to that possessed by thermoplasticsthemselves.

In accordance with the present invention, the waste is substantiallyunsorted waste (SUW). In the following the term “substantially unsortedwaste” or “SUW” will be used to denote waste material (including solids)that is either unsorted, e.g. obtained as is, i.e. in the form it isreceived at a solid waste management facility or at a waste dump or froma landfill; or waste material from which one or more components areoptionally selectively removed before processing. Such components aretypically those that have an economical value as recyclable materials orarticles, which have not already been removed through recycling at thesource of the waste. Such components may include, without being limitedthereto, metal parts especially batteries, aluminum and iron, glass,ceramics, paper, cardboard and plastic containers such as bottles,storage bowls, commercial plastic ready to cook containers etc.Typically, the SUW used for subsequent processing to yield the compositematerial of the invention constitutes at least about 80% by weight ofthe original waste material and at times above 90% and even 95% of theoriginal weight of the waste material (namely the components that areremoved from the unsorted waste constitute, respectively, up to about20%, up to about 10% and up to about 5% of the original unsorted wastematerial). For clarity it is to be noted that the % content when made inreferences to the unsorted or SUW denoted the respective relativecontent (w/w) on a total dry basis, with water excluded.

The SUW used, according to the invention, may either be received priorto processing as a wet material (namely, including water and/ormoisture) or may be received as dry material. Drying may be achievedeither by placing the waste outdoors and allowing it to dry, under astream of dry air, in an oven chamber or by squeezing the liquid out. Inthe context of the present invention, drying includes removal of atleast 50% of the moisture, at times 60%, 70%, 80%, 90% and even, attimes, up to 95% of the moisture initially contained in the SUW. It isnoted that 100% percent of the moisture does not have to be removed andin some applications it is even preferred that some water remains in theSUW for the subsequent procedure for preparing the composite material.Typically, the SUW obtained after drying and used for preparing tocomposite material that is disclosed herein has water and optionallyother volatile liquids such as ethanol, at content in the range of about1% and about 11%. While not wishing to be bound by theory, it iscurrently believed that the residual remaining water content plays arole is the chemical process that occur that convert the dried orsemi-dried SUW into the composite material of the present invention.

As stated above, the SUW is generally municipal solid waste and mayinclude, for example, solid, semi-solid and/or fluid materials,resulting from human and animal activities and may originate frommunicipal waste, industrial waste (e.g. chemicals, paints, plastics,sand), agricultural waste (e.g. farm animal manure, crop residues),sludge, and may be waste including hazardous material, etc. The wastemay be decomposable combustible waste, such as paper, wood, fabric ornon-combustible waste, such as metal, glass, sand and ceramics. Thewaste may also originate from landfills including old landfills. One ofthe benefits of the invention is in reducing the contents of landfillsto produce useful products while at the same time reducing the volume ofthe landfill.

The composite material of the invention may comprise plastic in therange of between about 0 and about 40%, typically, however not exceedingabout 35% or even about 30% of the composite material. The amount ofplastic in some embodiments may be at least 1%, 3%, 5%, 10% or 15%; insome embodiments the plastic material may be in an amount less than 30%,25% or even less than 20%.

The composite material in some embodiments may comprise at least about10% organic matter (other than synthetic polymeric material), typicallyat least about 15%, about 20%, about 25%, about 30%, about 35% or evenabout 40%; in some embodiments the composite material may comprise up toabout 90%, typically less than about 85%, about 80%, about 75% or evenless than about 70% of organic matter.

According to some embodiments the composite material comprises at leastabout 1%, about 2%, about 5%, about 10% or at least about 15% ofinorganic matter; by some embodiments the composite material comprisesless than about 50%, about 40%, about 30% or even less than about 20% ofinorganic matter.

At times, the properties of the composite material may be fine-tuned byadding certain constituents to said material either during thepreparation thereof or after it is formed. A non-limiting example isactive carbon that may absorb some volatiles and thereby remove somemalodors. At times the SUW may be supplemented with somewaste-originating material. At times the waste may be supplemented withrecycled or virgin material.

The organic material may include, without being limited thereto, anymaterial that was or is living, such as garden waste (leaves, grassclippings, branches, hay, flowers, sawdust, woodchips and bark), foodwaste (fruit, vegetables, grains, meat, egg shells, bones, oil, fat, ordairy products) as well as others (paper, feces, dust, hair, wood ash).Since the composite material comprises organic material it inherentlycomprises fingerprints that are unique to materials of biological origine.g. DNA, proteins, chlorophyll and a high content of potassium,nitrogen and phosphorous etc. as compared to materials of syntheticorigin.

While the composite material typically comprises plastic material in therange of about 10-30%, a composite material of the invention may also beprepared in a method as described herein without any plastic matter. Forexample, the product of extruding corn flour or organic waste (withoutplastic), at a temperature of about 200° C., were found by the inventorto be flowable materials at a temperature of at least about 100° C. Whenas little as 10% wt. plastic was mixed with the organic waste, theextrudate could further be processed by injection molding to obtain acomposite material having similar mechanical properties as thoseobtained from SUW.

As used herein, the term “plastic” should be understood as having thegeneral meaning as known by those skilled in art.

Without being limited thereto, the plastic material typically comprisesplastic materials such as synthetic polyolefins (e.g. high densitypolyethylene (HDPE), low density polyethylene (LDPE), polypropylene(PP)), polyethylene terephthalate (PET); polystyrene (PS) (includinghigh impact polystyrene, HIPS), rigid and plasticized polyvinylchloride(PVC), ABS (acrylonitrile butadiene styrene), PU (polyurethane),polyamides (PA), and ethylene vinyl alcohol copolymers (EVOH).

The organic material in the composite material of the inventioncomprises organic fibers. While the term “organic fiber” may beunderstood to include organic fiber of natural as well as of synthetic(man made) fibers it is used herein to predominantly denote fiberscomprising cellulose, hemicellulose and/or lignin and combinations ofsame, all being from natural sources. The combination of cellulose,hemicellulose and lignin is referred to at times by the term“lignocellulosic biomass”. It is to be understood that in the context ofthe present invention, the term “lignocellulose” has the meaning asgenerally known by one skilled in the art. Other types of organic fibersthat may be present are viscose, cellulose and modified cellulose.

According to one embodiment of the invention, the composite material hasa surface energy that is above about 35 dyne/cm, preferably above about40 dyne/cm and even more preferably above 45 dyne/cm. For the sake ofcomparison, the surface energy of polyethylene is about 35 dyne/cm andof polypropylene is about 31 dyne/cm, and of Polytetrafluoroethylene(PTFE/Teflon) 18-20 dyne/cm.

It is well understood that in order for two materials to adhere to eachother their surface energies (surface tension), should be alike.

In other words, on a high surface energy material, a polar material willspread into a thin layer (or “wet-out”) to assure a stronger bond. Thecomposite material of the present invention has a surface energy that ishigher than polyolefins This relatively high surface energy of thecomposite material of the invention permits strong interaction at itssurface with other polar substances, such as paint, adhesives, wood,various stones and others.

In one embodiment, the composite material of the invention has a densityabove about 1.2 g/cm³, typically in the range of 1.2-1.7 g/cm³.

The composite material of the invention may also be characterized by itstensile modulus of elasticity (also referred to at times by the termselastic modules or tensile modulus). The tensile modulus of elasticityis generally defined by a material's resistance to be deformedelastically (i.e. non-permanently) when a force is applied to it. Thehigher the force required, the stiffer the material is. Typically, thecomposite material has a tensile modulus of elasticity above about 600MPa. Thus, the composite material of the invention when formed into astructure having a shape such a rod, plank or the like is characterizedby stiffness comparable to that of other stiff thermoplastic materialssuch as polystyrene, polycarbonate, polymethylmethacrylate, (PMMA),polyethylene and others.

The composite material of the invention may also be characterized by oneor more of the following characteristics:

-   -   Tensile strength, namely, the stress at which a material fails        or permanently deforms under tension. Typically, the tensile        strength of an injection molded composite material of the        invention is above about 5 MPa, 6 MPa, 7 MPa and even above 8        MPa;    -   Flexural strength (also referred to at times by the term bend        strength), namely, the stress applied to a material at its        moment of rupture. Typically, the flexural strength of an        injection molded composite material of the invention is above        about 7 MPa, above about 9 MPa and even at about 11 MPa.    -   Flexural modulus refers to the material's stiffness in flexure,        namely, its resistance to deformation by an applied force.        Typically, flexural modulus of an injection molded composite        material of the invention is above about 2,000 MPa, above about        3,000 MPa, and even about 3,500 MPa.    -   Impact strength (notched Izod impact), refers to the ability of        a material to withstand shock loading. Typically, the impact        strength of an injection molded composite material of the        invention is above about 12 J/m, above about 13 J/m, 15 J/m and        even of above about 17 J/m.    -   Charpy Impact (Charpy V-notch test) refers to the energy per        unit area required to break a test specimen under flexural        impact. Typically the Charpy impact of an injection molded        composite material of the invention is above about 1.5 KJ/m²,        1.6 KJ/m², 1.7 KJ/m², or even 1.8 KJ/m².

Where metal is retained in the SUW and not removed prior to furtherprocessing, the mechanical properties including tensile strength,flexural strength, flexural modulus, impact strength and Charpy Impact,may be improved. The mechanical parameters may also vary by the finedetails of the manufacturing process. The process parameters may, thus,be fine-tuned to yield quantitatively different mechanical propertieswithin the range defined above. It is to be noted that the value of themechanical properties measurements may also, at times, change somewhatfrom one measuring equipment to another.

-   -   Odor profile (volatiles profile), refers to the mixture of        volatile compounds that are present in the composite material        which are released therefrom and contribute to the specific odor        of the composite material. The odor profile may be determined by        a head space GCMS test as detailed infra. Each compound of the        volatile profile may be present in varied quantities but not        less than a detectable amount in a head space GCMS test.        Typically, the volatiles profile of the composite material of        this invention comprises a combination of many of typical        compounds that are part of the odor profile of plastic and        organic waste, and in addition several compounds that are unique        to the composite material comprising butanone, acetic acid,        butanoic acid, furfural, and phenol (unless an odor absorbent is        present). Notwithstanding the above, several compounds which are        typical components of the volatiles profile of organic waste or        plastic are absent from the volatiles profile of the composite        material such as dimethyldisulfide, 2-pentyl furan,        benzaldehyde, and limonene. It should be noted that these        volatiles profile may vary by addition of odor absorbent or by        varying the reaction conditions temperature, initial moisture        content in the SUW or venting.

The composite material according to the invention is typically obtainedthrough processing of SUW. In one embodiment, the SUW comprises organicmaterial and plastics.

It has been found, in accordance with the invention, that the novelcomposite material possesses a dark color. Without being bound bytheory, it appears that the dark color is associated with a certaincomponent or components which firmly adhere to other components of thecomposite material. It is to be understood that in the context of thepresent invention a dark color means that the composite material absorbsall or almost all wavelengths of the visible light spectrum or, in otherwords, does not emit or reflect light in any or almost any part of thevisible spectrum.

It is noted that when fractionated into components by a variety offractionation techniques, dark-colored component(s) appeared to remainassociated with many of the fractionation products.

Without wishing to be bound by theory, the dark color seems to be aresult of reactions of or between various food residues during theformation of the composite material.

In accordance with an embodiment of the invention, the compositematerial having the thermoplastic properties has a substantiallycontinuous medium when viewed at a magnification that reveals structureshaving a size of above about 0.1 μm. The term “substantially continuousmedium” should be understood as referring to a dense compactedparticle-containing medium without significant gaps (voids) that may bedetected. For example, when sectioning the material and viewing thesections under a microscope, typically an electronic microscope, at themagnification that reveals structures of a size above about 0.1 μm nogaps are observed. It should be understood that the substantiallycontinuous particle-containing medium may contain some voids such as,for example, voids of trapped gas, trapped water vapor, gaps formedbetween solid micro-particles, etc. The continuous medium usuallyincludes also particles and the other materials of the medium are thentightly compacted around the particles, essentially without gaps, at theaforementioned magnification. It is noted that many of the particles arefibrous in shape. In one preferred embodiment, the substantiallycontinuous medium comprises particles of material substantially evenlydistributed there through.

The term “essentially without gaps” should be understood as meaning thata few or only small gaps will be seen at said magnification. It shouldbe understood that at higher magnifications, some additional gaps may beseen. Again, not wishing to be bound by theory, such tight interactionmay be attributed to surface adherence properties of the novelcomposition of matter of the invention.

In accordance with another embodiment of the present invention, thecomposite material flows at a temperature lower than that of commercialthermoplastic materials having relatively low melting points, such ashigh density (HD) or low density (LD) polyethylene (PE). In accordancewith some embodiments of the invention, the novel composite materialturns into a flowable material (moldable, malleable, remoldable,extrudable etc.) at temperatures below 130° C., at times below 125° C.,120° C., 115° C., 110° C. and occasionally even below 105° C., 100° C.,95° C. or 90° C. This means that the composite material of the inventioncan be initially formed into pellets and the like and stored beforefurther processing into usual articles. The further processing mayinclude injection molding, compression molding or other articlefabricating processes. Further processing may also include mixing virginor recycled plastic with the composite material which may be in the formof pellets or in any other suitable form. This mixture can then beformed into usable objects.

In accordance with another aspect of the invention, there is provided amethod of processing waste material, comprising: drying andparticulating substantially unsorted waste (SUW) that comprises organicmaterial and plastics to obtain dried particulate waste material;heating under shear forces the dried particulate waste material, to amaterial temperature of at least about 100° C., preferably above 115°C., 120° C., 125° C. and above; whereby a resulting composite materialwith thermoplastic properties is obtained and collected. Sufficientshearing, mixing and time are generally required so as to allow theentire waste mass to reach the indicated temperature. It is thusgenerally preferred to add heat to the process and not to rely solely onfrictional heating caused by the shearing and mixing. Thus, according toone embodiment, the dried particulate waste material is heated to atemperature of between about 100° C. and 240° C., and preferably to atemperature of between about 120° C. and 220° C., or between 180 and220° C. while being subjected to high shear forces such as obtainedusing a screw extruder as more fully described hereinafter.

As indicated above, the term “dried particulate” means waste that hasbeen reduced in size and at least some amount of volatile liquids (i.e.liquids having a vapor pressure of at least 15 mmHg at 20° C., e.g.water and ethanol) have been removed therefrom. The term “driedparticulate” should not be interpreted as describing completely driedparticles. On the contrary, it was found and that in order to producethe composite material having the properties as described herein, it isoften desired to maintain some level (e.g. above 1%) of water in theparticles. The amount of liquid removed from the SUW can be controlledand may be fine-tuned to the intended use of the eventually obtainedcomposite material. Particulating may precede drying or vice versa andthe drying step may include a sequence of drying, particulating, furtherdrying and further particulating etc. A sequence of a few cycles eachincluding a particulating procedure and drying (in this or the oppositeorder) may be useful, under some embodiments, to yieldinitially-processed SUW that is usable as a starting material forpreparing the composite material of the present invention, with afine-tuned content of water and/or other volatile liquids.

The dried particulates, when heated under shear forces at a temperatureabove 130° C. are considered, in the context of the present invention,sterile particulates, meaning that pathogens contained in the waste suchas germs, viruses and bacteria are destroyed.

The particulating of the SUW (either while drying or before or afterdrying) may take place by granulating, shredding, chopping, dicing,cutting, crushing, crumbling, grinding etc. A variety of devices areavailable in the art for particulating waste material such as shredders,grinders, chippers and granulators. Due to the presence of metal glassclay and stones in the SUW it is preferable to use blades or plates thatare made of robust materials such as stainless steel or titanium.Typically, the heating under shear forces of the dried particulatedwaste takes place in a compounder, including, without being limitedthereto, an extruder, an internal mixer (Banbury), a co-kneader,continuous mixer etc. It is preferable that the compounder providessufficient shear and mixing time so that the composite materialcollected upon cooling is essentially evenly dispersed matter throughoutthe mass/body of the composite material.

An extruder typically comprises a heated barrel containing rotatingtherein a single or multiple screws. When more then a single screw isused, the screws may be co-rotated or counter-rotated. Screws may beintermeshing, or non-intermeshing. The extrusion apparatus may be asingle extruder or combinations of extruders (such as in tandemextrusion) which may be any one of the extruders known in the plasticsindustry, including, without being limited thereto, single screwextruder, tapered twin extruder, tapered twin single extruder, twinscrew extruder, multi-screw extruder. A specific type of extruder in thecontext of the invention is a single screw extruder. In some embodimentsthe extruder is equipped with a venting zone. In some embodiments thenozzle of the extruder is chilled during the extrusion process.

In some embodiments, the particulating also includes separating from theparticulated matter elements of economical value and/or including, asdiscussed above, recyclable material or articles, such as batteries,aluminum and iron, glass, ceramics, paper, cardboard etc. The separationfrom the particulate matter of such elements may be executed by the useof suitable sieves, magnetic separators, eddy current separators,floatation systems, etc.

In accordance with some embodiments, the resulting composite materialmay be reheated to a temperature above 100° C., above 130° C. and evenabove 180° C., at which it turns into soft, flowable matter and thematerial can then be, extruded, reshaped, remolded, etc to a desiredshape. For example, in this manner, articles of a defined configurationmay be manufactured. For example, flower pots, housing siding, deckmaterials, flooring, furniture, laminates, pallets, septic tanks and thelike can be prepared, e.g. by further processing the composite material.

In one embodiment, the resulting composite material may be reheatedunder shear forces more than once, to yield a composite material havingproperties in the described range. The conditions under whichreiteration of the shearing and heating step is performed may the sameor different as those which were applied in the preceding shearing andheating. In any case, the reiteration is performed under the range ofconditions described above.

Various additives, fillers, etc., may be added to the reheated compositematerial, or even when the dried particulates are heated under shearforces, to impart certain desired properties to the article eventuallyobtained after cooling. Examples of fillers may include, without beinglimited thereto, sand, minerals, recycled tire material, concrete,glass, wood chips, thermosetting materials, other thermoplasticpolymers, gravel, metal, glass fibers and particles, etc. These fillersmay originate from recycled products, however, virgin materials may alsobe employed. Other additives may be added to improve the appearance,texture or scent of the composite material such as colorants, odormasking agents (e.g. activated carbon), oxidants (e.g. potassiumpermanganate) or antioxidants. Nonetheless it is noted that theproperties of the composite material of the present invention and itspotential uses are attained without the need to use binders orplasticizers although these may be added under some embodiments.

In certain embodiments of the invention there is also provided a methodfor preparing an article that has a defined shape, whereby waste,preferably SUW, is processed in a manner as defined above; and theneither while maintaining the temperature of the resulting material above100° C. or following re-heating of the material to a temperature above100° C., the material is molded to assume the desired configuration. Insome embodiments, the method may comprise preparing an articlecomprising two or more materials adhered to one another to formlaminates and the like.

In accordance with another embodiment of the invention, the novelcomposite material may itself serve as a filler or additive in themanufacture of an article, e.g. to be added, for example, to athermoplastic hot melt comprising for example a virgin or recycledplastic. It has been found that when using the novel composite materialof the invention as an additive for virgin plastics, the resultingmaterial can be molded using less energy for filling and cooling themolds. It is thus believed that using the composite material of theinvention may reduce process time as well as energy consumption inmanufacturing processes of various end products.

The composite material of the invention as well as the material obtainedby mixing the composite material with a plastic may thus be processedthrough a variety of industrial processes, known per se, to form avariety of semi-finished or finished products. Non-limiting examplesinclude building material, panels, boards, pallets, pots, component ofplant growth substrate, and many others. In such semi-finished orfinished products, the composite material of the invention may be thesole component or may be in a mixture with other materials. Inaccordance with the invention the products may include also laminatesadhered to each other, where at least one layer comprises the compositematerial of the invention. Such multi layer structures may be obtainedby lamination, co-calendering, co-compression, co-extrusion or tandemextrusion of two or more materials (one being the composite material ofthe invention) so as to form the multi-layer product.

The invention also provides a method for compacting waste comprisingdrying and particulating SUW, such as MSW, that comprises organicmaterial and plastics to obtain dried particulate waste material;heating the dry particulate waste to a temperature of at least about100° C., preferably above 130° C., under shear forces to obtain aresulting material; and preparing blocks of the resulting material. Insuch compacting, the material may be processed in a batch or continuousmanner and be formed into blocks or other shapes. A typical example isthe processing of the waste by extrusion.

In another embodiment, the composite material, especially ifsubstantially metal and glass-free, may be burned to provide an energysource.

According to another aspect of the invention, there is provided a methodfor preparing a processed material having one or more of the followingproperties at room temperature:

-   -   having a phase transition from a solid to a flowable state        (namely a state in which the material loses some its rigidity,        becoming softer and can be formed so as to change state without        breaking) at a temperature less than about 120° C.,    -   having a density above about 1.2 g/cm³,    -   having a surface energy above about 35 dyne/cm,    -   having potassium content above about 1 mg/g,    -   having tensile strength of above about 4 MPa,    -   having a tensile modulus of elasticity (tensile modulus) of        above about 600 MPa,    -   having flexural modulus above about 800 MPa or 1000 MPa,    -   having flexural strength above about 7 MPa or 10 MPa,    -   having notch impact strength above about 12 J/m,    -   having Charpy impact of above about 1.5 KJ/m², 1.6 KJ/m², 1.7        KJ/m², 1.8 KJ/m² or 2.0 KJ/m².    -   releasing volatile compounds comprising one or more of butanone,        acetic acid, butanoic acid, furfural, and phenol. These        volatiles have a characteristic odor which may be controlled by        adding absorbents such as active carbon.

In accordance with this aspect of the invention, the method comprisesdrying and particulating substantially unsorted waste that comprisesorganic material and plastics to obtain dried waste material and heatingthe dried particulate material under shear forces to a temperature of atleast about 100° C., preferably above 130° C., thereby obtaining theprocessed material.

The invention also provides a method for compacting waste, comprising:drying and particulating substantially unsorted waste that comprisesorganic material and plastics to obtain dried particulate wastematerial; heating the dry particulate waste to a temperature of at least100° C. material under shear forces to obtain a resulting material; andpreparing blocks of the resulting material.

DETAILED DESCRIPTION OF NON-LIMITING EXAMPLES Example 1 Processing ofDomestic Waste into a Composite Material

Processing Equipment

In the following processes various devices and systems were employed. Itis to be understood that while some of the devices were constructed bythe inventor, all are based on conventional devices. These include ashredder, a single screw extruder, a compounder (Banbury), an injectionmolding machine, a compression molding press and any other machine inwhich the material undergoes shearing and/or heat, such as a granulator,pelletizing press, mill etc.

Two single screw extruders were employed in the following examples. Thefirst is an self-designed extruder (screw diameter: 70 mm, screw length:2650 mm, clearance of screw to barrel: 0.1 mm, die and adapter length190 mm, die opening diameter: 10 mm) and the second is an Erema RM 120TE (screw diameter: 120 mm, screw length: 4000 mm, clearance of screw tobarrel: 0.1-0.2 mm, die and adapter length 370 mm, die opening diameter:50 mm), both having a venting zone.

Procedure

(i) Preparation of Extrudate

Substantially unsorted waste (SUW), collected from private householdswas shredded in a shredder equipped with titanium blades and then groundinto particles of a size of between several microns to severalcentimeters. The ground particulates were then air dried for a few days,dried under a stream of dry air, until at least some, but not all liquidwas removed (herein referred to by the term “dried particulates”). Thedried particulates were fed into single screw extruder that was set at atemperature along the extruder being higher than 150-180° C. but notmore than 210° C. The rotation rate of the screw in the extruder was60-90 rpm. The particulated material was processed in the extruder witha residence time of less than about three minutes. The extrudate wascooled to room temperature (herein “extrudate I”). Visual inspection ofthe extrudate suggested that it contains fibrous material as well assubstances having a melting point higher than the process temperature(e.g. glass and metal).

(ii) reparation of Extrudate II

Substantially unsorted waste (SUW), collected from private householdswas shredded in a shredder equipped with a titanium blades and thenground into particles of a size of between several microns to severalcentimeters. The ground particulates were then sieved to collectparticulates in the range of 100-200 mm in diameter. The 100-200 mmparticulates flow passes through a magnet that removes at least some ofthe original magnetic metallic content of the SUW. After separation ofmagnetic metals the remaining particulate flow is ground and sievedagain to obtain particulates having an approximate size of 20 mm. Theground particulates were then air dried for a few days, dried under astream of dry air, until at least some, but not all liquid was removedto obtain dried particulates. The dried particulates were fed intosingle screw extruder (Erema or the home-made extruder) that was set ata temperature of 180° C. and a rotation rate of about 50 rpm. Theparticulated material was processed in the extruder with a residencetime of between about 3 minutes to about 5 minutes. The extruder nozzlewas cooled in order to increase the pressure and the shearing force inthe extruder. The extrudate was cooled to room temperature (herein“extrudate II”). At times the extrudate was Visual inspection of theextrudate suggested that it contains fibrous material as well assubstances having a melting point higher than the process temperature(e.g. glass and metal).

Preparation of Moldings, Granules and Test Specimen

The extrudate (either extrudate I or extrudate II), before cooling, wassubjected to hot compression molding or cold compression molding afterit was cooled. At times, the extrudate were granulated (herein “thegranules”).

Further alternatively, when indicated, the granules were subjected toinjection, rotation or compression molding to obtain test specimens(herein “the test specimen”).

The extrudate and its processed variations (i.e. the granules, and thetest specimens) had a unique dark color and were found to beunexpectedly stiff.

Example 2 Characterization of the Composite Material

Composition Analysis

1. Extraction of Extrudate I in Organic Solvents

The extrudate I was subjected to a series of consecutive extractionsusing different solvents where each extracted fraction was then analyzedby various spectral techniques; NMR, (Avance 200 and 400 MHzinstruments), IR, TGA, elemental analysis, and ICP, (the results are notshown but discussed below).

FIG. 1 outlines the extraction steps. Specifically, 10 g of the preparedextrudate were refluxed for 24 hours in a Soxhlet apparatus in xylene.7.1 g of insoluble material (1^(st) residue) remained in the thimble.The filtrate extract (1^(st) extract) was green. On cooling to roomtemperature (RT) a precipitate (2^(nd) precipitate) formed. On filteringand drying this yielded grey flakes (2.0 g). The second filtrate wasdistilled to remove the xylene, leaving a residue of green flakes (0.8g) in the flask. Analysis (FTIR, Bruker Alpha P instrument), NMR (Avance200 and 400 MHz instruments) and elemental analysis (Spectrolab, Rehovotaccording to AOAC International method 973.18 for Fiber and Lignin)suggested that the grey flakes are primarily polyolefins such aspolyethylene and polypropylene. The xylene was evaporated from the 2ndfiltrate to yield 0.8 g green flakes. Analysis (according to thetechniques described above) suggested that these green flakes comprisehigh impact polystyrene (HIPS), oxidized PE, and some traces ofchlorophyll denaturant.

The insoluble 1^(st) residue from the reflux with xylene extraction wasfurther processed. Specifically, the 1st residue was refluxed intrichloroethanol (TCE) for 20 hours in a Soxhlet apparatus. A 3^(rd)insoluble precipitate produced was removed by filtration yielding 3.76 gof black lumps-like compact masses (“Black Lumps (A)”).

The reflux in TCE also produced a 3^(rd) soluble filtrate which wasallowed to cool to room temperature (RT). As a result, a 4^(th)precipitate and 4^(th) filtrate were formed. The 4^(th) precipitate alsohad the appearance of black lumps (“Black Lumps (B)”) and weighed 1.15g. TCE was evaporated off the 4^(th) filtrate to yield 2.55 g of blackpowder. The black powder received from the 4^(th) filtrate and the blacklumps received from the 3^(rd) and 4^(th) precipitate were identified ascomprising lignin, cellulose and soluble fibers (the cellulose andlignin analyses were conducted according to AOAC International method973.18 for Fiber and Lignin, which distinguishes between cellulose andlignin).

Thermogravimetric analysis (TGA, TA Instruments TGA 2050) revealed 10%,48% and 31% of incombustible residues in each of 4^(th) filtrate, 4^(th)precipitate and 3^(rd) precipitate, respectively (as shown in FIG. 1)that are attributed to silica, metals, clay, and other inorganic matteroriginally in the waste, as determined by the ICP tests. A TGA analysison the non-extracted unsorted waste gave a value of 24% incombustibleresidues.

The composition of the extrudate was determined using FTIR, NMR,elemental analysis etc. The results show that it contained about 28%plastics, about 55% cellulose material and about 20% metals glass andbiomass other than cellulose.

2. Extraction of Extrudate I in Hot Water

Hot water extractions were performed on a different sample of theextrudate I, where concrete and tuff (volcanic ash) were used ascontrols. Specifically, extrudate, concrete or tuff were subjected towater reflux for 24 hours after which the following parameters weremeasured in the water: Total Organic Carbon (TOC); Dissolved OrganicCarbon (DOC); Total Dissolved Solids (TDS); Total Organic Halides (TOX);Phenol Index (PI); Polycyclic Aromatic Hydrocarbons (PAHs);Benzene/Toluene/Ethylbenzene/Xylene (BTEX) and Anions. The results ofthe analysis are provided in Table 1.

TABLE 1 Analysis of hot water extractions TOC DOC TDS TOX PI PAHs BTEXAnions¹ Sample (mg/g) (mg/g) (mg/g) (μg/g) (μg/g) (μg/g) (μg/g) (mg/g)Extrudate 7 16 18 <5 <5 0.015 0.07 2.257 Concrete 0.62 17 21 <5 <5 nd0.08 3.37 Tuff 0.16 0.38 3 <5 <5 nd 0.05 0.589 ¹The main anions thatwere found were Cl—, F—, NO₃—, and SO₄— nd = not detected

In addition, NMR and FTIR provided evidence for the existence ofcarboxylate groups which without being bound to theory may originatefrom sodium polyacrylate degradation products, from diapers orcarboxylic acids derived from natural sources (e.g. ascorbic acid fromfruits, acetic acid due to fermentation and oxidation of sugars).

3. Ion Content of the Extrudate Following Extraction in Hot Water

The inorganic content of extrudate I and II (digested by concentratednitric acid and exposed to 650 watt microwave radiation for 10 minute)or granules following extraction in hot water was also determined, usingInductively Coupled Plasma (ICP) elemental analysis and the results arepresented in Table 2. Non-treated flakes were used as control.

TABLE 2 Inorganic content in extrudate I, extrudate II and hot waterextracts of extrudate I, granules, concrete and tuff Sample Ca Fe Na AlK Mg P Zn Si S Extrudate I (mg/g) 32 4.4 7 13.9 5.64 6.14 0.66 0.36 71.30.74 Extrudate II (mg/g) 24.7 6.54 27.8 10.5 2.19 2.47 1.01 0.36 7.471.12 Hot water extract of 0.75 0.01 0.48 0.01 0.36 0.07 0.02 0 0 0.13extrudate I (mg/g) Hot water extract of 1.06 0.14 3.84 0.01 1.89 0.150.12 0.01 0 0.02 granules (mg/g) Hot water extract of 0.63 0 0.16 0.230.37 0 0 0 0 0.58 concrete (mg/g) Hot-water extract of 0.24 0 0.12 0.010.04 0 0 0 0 0.06 tuff (mg/g)

It has been found that both the two extrudates and the granules haverelatively high potassium content, in the range of milligrams per gram.The two extrudates and the granules had 5.64 mg/g 2.19 mg/g and 1.32mg/g of potassium content, respectively (the difference probably arisingfrom different sources of SUW). It has thus been suggested that thishigh potassium content can be a fingerprint for products of theinvention as this relatively high potassium content is not expected tobe found in products produced from virgin synthetic polymers. The maindifference between the two extrudates lies in the silicon content theyexhibit which may be attributed to a higher amount of sand in the SUWbatches which were used to prepare the extrudate I samples.

4. DNA Analysis

DNA was detected in the composite material. To this end, DNA wasextracted from 50 mg specimens taken from (1) dried granulated SUW and(2) ground extrudate II using a Stool DNA extraction kit (Bioneer,Korea) Sample (1) was taken from dried granulated extrudate II; sample(2) is a positive control; sample (3) is a negative control and sample(4) was taken from dried granulated SUW. The samples were then mixedwith PCR ready mix and inserted to PCR. The DNA extract from each samplewas dyed with ethidium bromide (EB) and then subjected to gelelectrophoresis. The gel was trans-illuminated with ultraviolet lightwith a peak wavelength of 340 run and the resultant fluorescence ofdouble stranded nucleic acid was observed at a peak wavelength of 610nm.

Columns 1-4 correspond to samples (1)-(4) respectively and Column M isDNA MW reference. FIG. 2 shows that samples (1) and (4), bothoriginating from SUW contained DNA. No evidence of DNA was observed withrespect to Sample (3) which contained the negative control. The factthat the product of the invention (sample (1) contains DNA may be usedas a fingerprint for distinguishing products from SUW with thoseobtained from sorted waste. Only biological matter that can be found inunsorted domestic waste (such as food, plants, meat remains andmicroorganisms that are known to be present in waste fermentation) canbe the source of this type of DNA.

Physical Analyses of Extrudate I

1. Thermogravimetric Analysis (TGA)

The measurements were conducted on a Thermal Gravimetric Analyzer—TAInstruments, TGA 2050, at 20 C/min heating rate in air environment.Specimens were taken from an injection molded product (series 1) and acompression molded product (series 2) that were produced from twodifferent batches. The specimens were powdered and subjected to TGAtesting that measures any loss of weight (e.g. as a result of vapor,combustion etc) as a function of temperature at a given heating rate.

Results are depicted in FIG. 3, showing weight loss % vs. temperaturecurves, and in FIG. 4 the first derivative of weight loss/temperature,as function of temperature. The peaks shown in FIG. 4 at 170, 320° C.correspond to natural organic matter (such as cellulose) and the highertemperature peaks at 360, 450, 485, 510 and 535° C. are typical ofsynthetic polymers. In addition, there is always a residual inorganicfraction (20-25%) that does not vaporize or turn into carbon dioxide.The TGA curves of the injection molded product and the compressionmolded product in FIGS. 3 and 4 are slightly different, mainly in thepeak ratio of the peaks at 360, 450, and 485° C., while the peak at 510°C. is completely missing from the compression molded product. Thesedifferences are a result of differences in the plastic composition (suchas PP, PE, etc.) between the two batches.

2. Measurement of Various Physical Characteristics

Test specimens were subjected to a series of analyses by knowntechniques in order to determine their physical properties, includingDensity, Surface Energy; Adhesion, Thermal Expansion Coefficient,Specific Heat, Water Absorption, Limiting Oxygen Index, Inorganicelements content.

Density was determined by measuring the dimensions of a flat square toobtain the volume and weighing using a Mettler analytical balance. Thedensity is the mass in grams divided by the volume in cubic centimeters(g/cc)

Surface energy measurements were performed according to the proceduredescribed in ASTM D2578-84.

Adhesion to the surface of an injected strip was tested using variousadhesives, including epoxy, Loctite® cyanoacrylate, rubber adhesive,Polyester adhesive as well as to that of polyurethane paint.Specifically, the various adhesives were applied on the surface ofindividual extrudates onto which sheets of aluminum foil wererespectively placed. Adhesion of the aluminum foil to the extrudates andthin strips of aluminum foil were pressed onto the adhesive so that anon adhered tail of aluminum strip remained. After drying for 24 hoursthe tail of the aluminum foil was tugged to try to separate the adhesivefrom the extrudate. The paint and adhesives remained firmly attached tothe injected strip. This illustrates that the composite material has amuch better surface for adhesion than most common plastics such aspolyethylene.

Specific Heat was measured by differential scanning calorimeter.

For determining the limiting oxygen index a test specimen was positionedvertically in a transparent test column and a mixture of oxygen andnitrogen was forced upward through the column. The extrudate was ignitedat the top. The oxygen concentration was adjusted and decreased untilthe combustion of the extrudate was arrested. The minimum concentrationin volume percent of oxygen that supported flaming combustion wasdetermined as the limiting oxygen index (LOI).

Inorganic elements content was measured by ICP spectroscopy.

Comparative results are provided in Table 3, below.

TABLE 3 Physical characteristics of extrudates Characteristic ExtrudateI Wood Iron Concrete Polypropylene Density (g/cm³) 1.55 0.18-0.82 7.862.4  0.9 Surface Energy (dyne/cm) 44-46 30-40 nd >45.6 20-25  SpecificHeat (kJK⁻¹Kg⁻¹) 4.4¹ 1.26² 0.45² 0.8² 1.7-1.9² Limiting Oxygen Index,(%) 22 21 N/A N/A 17.5 Inorganic elements, (ppm) >20,000 nd 100 ndtraces nd = not detected; N/A = not applicable ¹At 80° C. ²At STP:Standard temperature and pressure, being according to the NIST's version20° C. and an absolute pressure of 1 atm.

The results presented in Table 3 show that extrudate I has a density of1.55 g/cm³. This density is significantly distinct from cellulosicmaterials such as wood, paper, as well as from polypropylene (PP). PP isa representative of thermoplastic polyolefins having densities below 1g/cm3.

Table 3 also shows that extrudate I has a surface energy between 44 and46 dyne/cm, which is similar to the surface energy of polyesters,epoxies or polyurethane. When comparing to the surface energy ofpolyolefins, the latter can reach the value of the extrudates only ifthey are mixed with suitable additives.

3. Dynamic Mechanical Thermal Analysis (DMTA)

Test specimens were also subjected to DMTA (Perkin Elmer DMA 7e).Specifically, injection molded extrudate (injection at 180° C.) orcompression molded waste, (i.e. not processed as described above andused as a control) were placed in a DMTA heated at 2° C./min, andtwisted at a frequency of 1 Hz.

FIGS. 5 and 6 show the storage modulus and loss modulus, respectively,of an injection molded test specimen (continuous line) and a compressionmolded test specimen (dashed line) as a function of temperature. Thestorage and loss modulus measure the stored energy during a cycle(representing the elastic portion), and the energy loss, dissipated asheat (representing the viscous portion).

4. Flexural Strength and Flexural Modulus

The flexural strength and flexural modulus of an injection molded testspecimen were measured using a Universal Tensile Tester, Instron 5568instrument and were found to be 21 MPa and 3,500 MPa, respectively.

5. Impact Resistance

The impact strength (Notched Izod Impact) of the injection molded testspecimen was measured using an Izod Impact Tester (Zwick). FIG. 7 showsthe room temperature impact energy for various test specimens preparedby injection molding at temperatures between 160° C. and 220° C.

6. Rheology

The apparent melt viscosities of ground extrudate samples weredetermined using a Capillary Rheometer (Goettfert, Rheo-Tester #1000).The ground extrudate was fed into a temperature-controlled barrel at thetemperature specified below, and forced through a capillary die (2 mminner diameter×30 mm long). The steady force for a given extrusion ratewas recorded. FIG. 8 provides the calculated apparent viscosity of thetested material as a function of shear rate, at 100° C., 120° C., 150°C. and 180° C. The behavior exhibited in FIG. 8 is typical ofpseudoplastic thermoplastic materials, where the viscosity decreasesupon increasing the shear rate.

7. Brabender Plastograph Test

Brabender Plastograph was used in order to determine the viscositychanges during the processing of fresh dried ground waste (“driedparticulated waste”, “DPW”) at different temperatures. Accordingly,samples of dry waste were mixed in a Brabender mixing cell at differentmachine temperatures of 70° C., 100° C., 150° C., 210° C. and 240° C.and at a rotor speed of 80 rpm or at 70° C. or 100° C. with a rotorspeed of 40 rpm for 30-60 minutes (until the torque reached a relativelysteady state). The torque and the temperature of the material wererecorded as a function of time throughout the process. It is noted thatthe torque correlates with changes in the viscosity of a material, whichenables the variation in viscosity of the ground waste processed in theBrabender to be tracked throughout the process.

It is noted that below 70° C. and 80 rpm, rapid plastification of theblend was observed by a temperature build-up associated with theviscosity decline, this being similar to thermoplastic behavior.Interestingly, this occurred before other thermoplastic materials, suchas PE, present in the blend, started to melt. Once PE melted, theviscosity of the blend increased. A viscosity decline was observed asthe temperature continued to increase.

It is noted that when testing the DPW at 70° C. and at 40 rpm no“fusion” of the extrudate particulates was observed (not shown). After60 minutes the blend appeared as pulverized solids, not generating anyinter-particle adhesion. At the rotor rotational speed of 80 rpm goodfusion of the extrudate was exhibited, wherein the material seemed tohave reached a temperature of 141° C.

The tests also exhibited that the temperature of the blend reached amaximum, and then started to decline. During temperature decline,viscosity (evidenced by torque) declined as well. Without being bound bytheory, this behavior may be explained by the partial hydrolysis of thewaste material increasing the fluidity of the composite material.

Table 4 summarizes parameters measured during the testing using theBrabender.

TABLE 4 Torque as a function of temperature and rotor speed MachineRotor Final Final Material Test Temperature Speed Torque TemperatureTime Material (° C.) (rpm) (Nm) (° C.) (min.) PP¹ 240 80 5.5 nd 24 DPW70 40 25 91-96 60 DPW 70 80 28.1 141 30 DPW 100 80 35.3 148 40 DPW 15080 30 (15)² 174 (165)² 40 (30)² DPW³ 200 80 12 208 60 Extrudate 200 8010 207 15 DPW 240 80 6.5 237 40 ¹Melt Flow Index of 2. ²Test on adifferent sample taken from a different batch DPW = dry particulatedwaste; nd = not determined

To summarize, Brabender tests that were performed on the dryparticulated waste (DPW) show a reduction in the final torque as afunction of the temperature of the Brabender, which is translated toreduction of viscosity with the increase of temperature. In all of thetests, the DPW exhibits a rapid fusion into processable flowable/softenblend similar to thermoplastic materials. These results are compatiblewith the behavior of thermoplastic materials.

Brabender Plastograph was also used to demonstrate the thermoplasticbehavior of the extrudate of the composite material. To this end, groundextrudate was mixed in a Brabender at 200° C., at a rotor speed of 80rpm for 15 minutes (FIG. 9A). Respective parameters for Polypropylene(PP), used as reference are also presented (FIG. 9B, 240° C., 80 rpm).The Brabender plastograph of the extrudate and that of polypropylene arealmost identical. Both exhibit a correlation between torque reductionand temperature elevation both of which reach a plateau after a veryshort blending period. Such similarity to the behavior of a “classic”thermoplastic material such as polypropylene provides further evidencefor the thermoplastic character of the extrudate.

8. Microscopy

The outer surface of extrudates was examined under light microscopy, atthree different magnifications (×50, ×100 and ×200). FIGS. 10A-10Cprovide three respective micrographs of the same area on the surface ofan extrudate. The micrographs reveal continuity of the matter formingthe extrudates, close contact between different substances in theextrudate and lack of apparent pores or gaps. Tightly embedded fibrousmatter is seen stretching throughout the imaged surfaces.

The inner structure of an extrudate material was studied by scanningelectron microscopy (SEM). To this end, an extrudate was immersed inliquid nitrogen and fractured in the frozen state. Another sampleobtained by compression molding of waste was treated similarly. SEMimages of cross-sectional freeze-fractures of the extrudate and thecompression molded samples are provided, respectively in FIGS. 11A-11B.In FIG. 11B the formation of regions of different formations are clearlyexhibited. The boundaries between three such regions, or domains, aremarked by respective three dashed lines, line A, line B and line C. Thefact that there are no gaps or cavities along the boundaries is evidencefor the close interaction between the different components. FIG. 11Ashows that the extrudate is a multi-component composite materialcontaining relatively large inclusions of irregularly shaped particles,200-250 μm, and fibrous inclusions, 50-100 μm diameter, the particlesand fibrous inclusions being dispersed in a continuous medium. Thismedium appears also to be a multi-component system comprising aplurality of particles of different shapes and sizes, down to 0.5-2 μm.The image also suggests that all components strongly interact one withthe other, forming a dense compacted matter, with no visual gaps betweenthe components.

It is noted that unless otherwise stated, the above experiments were notconducted according to ASTM.

9. Head Space Gas-Chromatograph Mass-Spectroscopy (HS-GCMS)

In order to characterize the unique volatile profile of the compositematerial of the invention, a sample from an extrudate of the compositematerial according to the invention (extrudate II, sample 1) wasanalyzed by HS-GCMS. The volatile profile of the extrudate of thecomposite material was compared to the volatile profile of organic wasteand of plastic waste, which are the major components comprised in SUWwhich contribute volatiles. To this end samples from organic waste(sample 2) and plastic waste (sample 3) components that were separatedout of SUW were also analyzed by HS-GCMS. Such a comparison provides aqualitative indication of the specific volatiles that are unique to thecomposite material that is the product of the described process.

The samples were ground into powder and placed in SPME GC-MS vials. Thevials were heated to 80° C. for 25 min and underwent SPME GC-MS analysison SGE BPX or TR-5MS columns. Helium was used as carrier gas and thetemp gradient 50° C.-240° C. at 10° C./min.

TABLE 5 Volatile profiles of the composite material extrudate andcomponents Frac- Retention Or- tion time Detected ganic Plastic Poly-Ex- No. (min) Compounds waste waste ethylene trudate 1 7.9 Acetone + + 28.93 Hexane + 3 9.55 2,3-Butanedione + + 4 9.8 Butanone + 5 10.81 Aceticacid + 6 11.80 Pentanal + + + 7 12.95 Dimethyldisulfide + 8 13.0Octane + 9 13.16 Toluene + + + 10 13.1-13.9 Pentanol + 11 13.92Hexanal + + + + 12 14.33 Butanoic acid + 13 15.27 Furfural + 14 15.28Hexanol + + + 15 15.91 Heptanal + + + 16 16.74 1-Decene + 17 16.8Decane + 18 17.16 2-Pentyl-furan + 19 17.4-17.5 Heptanol + 20 17.76Octanal + + + 21 17.83 Benzaldehyde + 22 18.02 Limonene + + + 23 18.5Undecane + + 24 18.2 2-Ethyl-hexanol + + 25 18.62 Phenol + 26 19.05Octenal + 27 19.47 Nonanal + + + + 28 20.09 Dodecane + + + 29 21.06Decanal + + + 30 21.58 Tridecane + + + + 31 22.541 Carvone + + 32 22.543Tetradecene + 33 23.11 Tetradecane + + + 34 24.79 Pentadecane + 35 26.69Hexadecene + 36 27.08 2,4-Di- + tertbutylphenol

Fractions No. 2, 7, 10, 18, 19, 21, 26, 34, 35 and 36 are compounds thatare released from one of the components of SUW that are not releasedfrom the extrudate. Fractions No. 4, 5, 12, 13 and 25, are compoundsthat are released only from the extrudate. The difference in thisrelease profile, using one, two or any number out of these 15 compoundsalone or in combination as a differentiating factor, may be used as oneof the characteristics of the composite material of the invention.

Reference is now made to FIGS. 12A-12D showing chromatograms of headspace gas chromatography mass spectroscopy (HS-GCMS) of solid phasemicro-extraction of an extrudate of the thermoplastic composite materialaccording to the invention (FIG. 12A); organic waste (FIG. 12B);unsorted plastic waste (FIG. 12C) and polypropylene (FIG. 12D). Table 5lists the compounds that were characterized by the MS of each GCfraction of each sample. As illustrated in FIGS. 12A-12D, and Table 5,significant differences are found between the samples. The most dominantpeaks for the extrudate are: acetone, pentanal, toluene, hexanal(dominant peak), butanoic acid, furfural, heptanal, and octanal. Thesepeaks correspond to degradation products of natural products (e.g. fattyacids).

Several typical volatiles of polyethylene, organic waste and plasticwaste are absent from the volatile profile of the extrudate. Forpolyethylene, these are for example 1-decene, decane, dodecene,tridecene, tetradecene (the dominant peak), pentadecene and hexadecene.These are all long carbon chain volatiles originating from various oilproducts. Without being bound to theory this may indicate that in theprocessing of the SUW, these long chains are entrapped within theresultant product or that PE is protected from decomposition.

On the other hand, several compounds are part of the volatiles profileof the extrudate whereas they are not part of either the organic wasteor the plastic waste profiles (dark background). These compounds arenamely butanone, acetic acid, butanoic acid, furfural, and phenol. Theirappearance in the volatile profile of the extrudate is a uniquefingerprint of the product. Without being bound to theory, this may beindicative of a degradation reaction of cell wall and membranecompositions.

In addition, the volatile profile of the extrudate also contains variouscompounds which point to the components comprised in the SUW. Forexample, the noticeable element in the plastic fraction,2-ethyl-hexanol, is a fatty alcohol with emulating properties known tobe in use as plasticizer. It could not be found within the organicfraction of waste. On the other hand, acetone and 2,3-butanedione canonly be found in the organic fraction of the waste material and they areindicative of the organic content within the extrudate. All together,these data are attributed to the unique odor profile of the compositematerial of the invention.

Example 3 Preparation of Extrudates Comprising Low or No Plastic Content

In order to find the plastic content threshold in SUW for making thecomposite material of the invention, extrudates that mainly containorganic waste were prepared. The extrudates were prepared according tothe method described for preparation of extrudate II (prepared by usingthe home-made extruder) except for using 100% organic waste (OW) withonly traces of plastic or a mixture of 90% OW and 10% recycledpolyethylene instead of using dried particulate SUW. Both mixtures alsocontained traces of sand. The OW was obtained from a farmers market,wherein substantially all plastic and inorganic waste was manuallyremoved therefrom.

One test sample of 100% OW extrudate was tested after it cooled down toroom temperature and a second test sample was compressed by a force of200 Kg in a compression mold. A sample of 100% unsorted polyethylene wasalso prepared for comparison.

The test samples of the OW/PE 90:10 and 0:100 were prepared by grindingthe obtained extrudate, and feeding the ground extrudate into a Demag,Ergotech Viva 80-400 Injection molding Machine.

The test exhibited that all three mixtures comprising organic waste atdifferent levels were processable and could be extruded. The 100% OWextrudate was susceptible to compression molding and when mixing with aslow as 10% PE (OW/PE 90:10) the extrudate was susceptible to bothcompression molding and injection molding. Specimens from the testsamples were analyzed according to the standard test listed in Table 6.

The mechanical properties of the injection molding test sample of OW/PE90:10 and the comparison test sample of 100% PE are presented in Table7.

TABLE 6 Standard procedures and equipment used for conducting themechanical tests presented in Examples 3-8 Test Description StandardEquipment Tensile Strength ISO 521-1-2 Testometric M350-10KN Elongationat Break ISO 521-1-2 Testometric M350-10KN Tensile Modulus ISO 521-1-2Testometric M350-10KN Flexural Strength ISO 178 Testometric M350-10KNFlexural Modulus ISO 178 Testometric M350-10KN Charpy Impact ISO 179Ray-Ran Density ISO 1183-2 Brabender-Densimat DM ThermogravimetricAnalysis ISO 11358 TGA Q500 TA

TABLE 7 Mechanical properties of test samples made of mixtures oforganic waste (OW) and polyethylene (PE) Max. Modulus Charpy Tensile ofElongation Flexural Flexural OW/PE TGA Impact Strength Elasticity atBreak Strength Modulus (%:%) (%) (KJ/m²) (MPa) (MPa) (%) (MPa) (MPa)0:100 24 N/A 10.42 276.18 676.17 8.20 194.09 90:10  28 2.1 2.67 328.4318.92 5.66 687.38

Example 4 Preparation and Properties of Extrudates Made of Mixtures ofthe Composite Material and Polyethylene

Extrudate of the composite material which was prepared according to theprocedure for preparing extrudate II as detailed above (using thehome-made extruder) was particulated sieved and sorted according to theparticle size to obtain composite material granules having a particlesize of between 1.8 mm and 2.5 mm and composite material dust having aparticle size of up to 0.7 mm. Particulated composite material granulesor dust were mixed in a blender with various quantities of recycledpolyethylene (PE). The combined composite material/PE mixture wasintroduced into a single screw extruder (dia. 70 mm) at 180° C., 50 rpmand a residence time of between 3-5 minutes. The resultant extrudate wasground, and fed into an injection machine (Demag, Ergotech Viva 80-400,temperature: 180° C., injection pressure: 60-90 bar, injection speed:30-50 mm/s). The mechanical properties of each injection molding arepresented in Table 8 and were determined according to the analysisstandards and equipment listed in Table 6.

TABLE 8 Mechanical properties of injection moldings made of mixtures ofthe composite material extrudate (Extrudate) and recycled polyethylene(PE) Max. Modulus PE/ Charpy Tensile of Elongation Flexural FlexuralExtrudate Impact Strength Elasticity at Break Strength Modulus Density(%:% wt) (KJ/m²) (MPa) (MPa) (%) (MPa) (MPa) (g/cm³) 100:0  N/A 10.42276.18 676.17 8.20 194.09 nd 90:10 N/A 9.93 330.74 191.15 6.97 249.89 nd80:20 N/A 9.83 328.50 122.02 10.10 308.93 nd 70:30 N/A 8.8 349.61 86.1310.48 364.18 nd 60:40 N/A 8.67 437.68 65.93 10.11 394.47 nd 50:50 N/A8.18 512.61 76.24 12.03 578.24 nd 40:60 16.03 7.90 627.01 44.36 13.32796.67 nd 30:70 9.80 7.02 714.68 1.8 14.99 989.3 nd 20:80 5.09 7.13794.13 2.27 12.66 1060.2 nd 10:90 3.32 6.53 979.6 2.22 8.75 831.0 nd  0:100¹ 2.22 5.92 1160.0 0.63 13.32 1934.5 1.35   0:100² 1.84 5.13997.9 7.71 7.68 830.0 1.35   0:100³ 1.39 5.60 951.55 0.34 11.08 1121.41.47 ¹Made of composite material granules that were dried at 100° C. for24 h before injection of the samples. ²Made of composite materialgranules that were injected as is (without further drying). ³Made ofcomposite material dust.

The results show that mixing the composite material extrudate withrecycled polyethylene results in injectable molded products havingmechanical properties that most of them are linearly correlated (exceptfor the elongation at break and flexural strength) with the ratiobetween the composite material and the recycled PE. The elongation atbreak significantly drops from 676.17% to 191.15% even when as little as10% composite material is present in the mixture. In addition, theflexural strength seems to reach a maximum for a PE/Extrudate 30:70mixture and a minimum for each of the components alone.

A dynamic (parallel plates) rheometer test at 200° C. was performed oneach on of the samples and demonstrated an inverse correlation betweenthe amount of PE and the viscosity of the test sample. Therefore,without being bound to theory it may be concluded that PE contributes tothe viscosity of the composite material. The recorded rheologicalbehavior shows clearly that the viscosity increased as the polyethyleneratio was decreased

Example 5 Preparation and Properties of Injection Molding Samples Madefrom Dried Particulated SUW with Various Unsorted Plastic (USP) Content

An extrudate was prepared according to the procedure for preparingextrudate II as detailed above (using the home-made extruder) except forusing mixtures of dried particulated SUW with unsorted plastic waste(USP) in varied ratios instead of dried particulated SUW. The USP wasreceived from a plastic recycling plant. Mixtures comprising driedparticulated SUW and USP in a weight to weight ratio of 100:0, 75:25,50:50, 25:75 and 0:100 were blended in a mixer until a homogenizedSUW/USP mixture was formed. The homogenized SUW/USP mixtures wereintroduced into the home made single screw extruder (dia. 70 mm) at 180°C., 50 rpm and a residence time of between 3-5 minutes. The resultantextrudate was ground, and fed into an injection molding machine (Demag,Ergotech Viva 80-400, temperature: 180° C., injection pressure: 60-90bar, injection speed: 30-50 mm/s) to obtain test samples. Specimens fromeach of the test samples were analyzed according to the standardprocedures and equipment listed in Table 6. The Mechanical propertiesare summarized in Table 9.

TABLE 9 Mechanical properties of injection molded samples made ofmixtures of dried particulated substantially unsorted waste (driedparticulated SUW) and unsorted plastic waste (USP) SUW/USP Max. Modulus[total Charpy Tensile of Elongation Flexural Flexural plastic] TGAImpact Strength Elasticity at Break Strength Modulus Density (% wt) (%)(KJ/m²) (MPa) (MPa) (%) (MPa) (MPa) (g/cm3) 100:0 [13] 79 1.66 6.25686.73 0.34 11.08 1121.4 1.39  80:20 [30]* na 2.18 5.96 1260.1 0.63 4.561277 nd 75:25 [35] 69 1.57 7.28 1264.6 0.28 14.30 1448.8 nd 50:50 [57]63 2.12 6.02 1344.4 0.45 13.11 1658.8 nd 25:75 [78] 80 2.82 7.03 1225.50.94 16.59 1854.2 nd  0:100 [100] 84 3.03 10.00 1435.3 1.20 18.34 1777.11.24 nd—not determined *prepared from a different SUW batch

Example 6 Mechanical Properties as a Function of Residential Time

In order to assess the effect of the residential time of the driedparticulated SUW in the extruder on the mechanical properties of theextrudate, the extrusion process was iterated several times, and themechanical properties of each extrudate were determined. To this end, anextrudate that was prepared according to the procedure for preparingextrudate II (using the home-made extruder) was reintroduced severaltimes consecutively to the singled screw extruder under the sameconditions. Each extrudate was sampled and characterized according tothe standard procedures listed in Table 6.

Table 10 summarizes the mechanical analyses of the test samples. It isclear from the results that several mechanical properties are improvedby iterating the residence in the extruder. While the mechanicalproperties improvement is most substantial after the third iteration, inmost parameters it became even-tempered between the third and the sixthiterations. The only parameter that continuously improves and that maybenefit from even further iterations is the modulus of elasticity whichincreases from 2970 MPa after the first extrusion to 4875 MPa after thefifth iteration.

Unlike other existing polymers in which their mechanical propertiesdegrade by such iterations, the injection molding of the compositematerial exhibited an improvement in its mechanical properties.

TABLE 10 Mechanical properties of iterative injection moldings made ofthe composite material Max. Modulus Charpy Tensile of ElongationFlexural Flexural Iteration Impact Strength Elasticity at Break StrengthModulus No. (KJ/m²) (MPa) (MPa) (%) (MPa) (MPa) 1 1.37 4.8 2970 0.2210.7 3350 2 1.73 5.7 3533 0.27 14.7 4075 3 1.49 5.6 4418 0.18 15.6 42894 1.30 4.9 4661 0.14 15.7 4788 5 1.37 5.6 4875 0.15 15.4 4584

TABLE 11 Testing procedures and instrumentation used for the mechanicalanalysis of the iterative extrusion injection moldings Test DescriptionStandard Equipment Tensile Strength ISO 521-1-2 Instron universalTesting machine Elongation at Break ISO 521-1-2 Instron universalTesting machine Tensile Modulus ISO 521-1-2 Instron universal Testingmachine Flexural Strength ISO 178 Instron universal Testing machineFlexural Modulus ISO 178 Instron universal Testing machine Charpy ImpactISO 179 Ceast Impact Pendulum

Example 7 Leaching Tests Performed on Compression Molding of theComposite Material

Leaching tests were performed on specimens taken from cold compressionmoldings of hot extrudate of the composite material. The tests wereconducted in accordance with the EN 12457/2 compliance test for leachingof granular waste materials and sludge.

The analysis was focused on detection of metal ions that leached fromthe test samples including As, Ba, Cd, Cr, Cu, Hg, Mo, Ni, Pb, Sb, Se,and Zn. The only metal ion that was found to be present above theinstrumental detection limit of 0.5 mg/Kg was zinc in a concentration of1.34-1.91 mg/Kg.

Example 8 Mechanical Properties as a Function of Liquids in the SUW

The effect of moisture content in the raw SUW on the mechanicalproperties of the composite material was tested. To this end, threeinjection molded samples of the composite material (samples 1-3)originating from the same SUW were tested. Sample 1 was prepared fromSUW that was air dried for three days, sample 2 was prepared from SUWwithout further drying, and sample 3 was prepared from the SUW after ithas been stored for three days in a closed storage chamber. All threesamples were prepared following the procedure described for extrudate II(using the Erema extruder).

The volatile liquids content of the each raw material was determined bythe weight difference before and after drying a specimen that was takenfrom the raw material for 24 hours at 60° C./30 mmHg. The loss of weightis attributed to removal of volatile liquids that were present in theSUW, especially moisture. Samples 1-3 had a volatile liquid content of1.81, 11.07 and 11.07%.

The mechanical properties of the three samples are presented in Table12. All three samples also had a surface energy of between 46 and 47.7dyne/cm (determined as described above). It is evident from themechanical properties analysis that the volatile liquids content as wellas the wet storage period has a remarkable influence on the mechanicalproperties of the product.

TABLE 12 Mechanical properties of injection molded samples of thecomposite material having different volatile liquids content VolatileMax. Modulus liquids Charpy Tensile of Elongation Flexural SurfaceSample content TGA Impact Strength Elasticity at Break Strength energyNo.: (%) (%) (KJ/m²) (MPa) (MPa) (%) (MPa) (dyne/cm) 1 1.81 34 1.85 4.49368.68 0.46 4.03 46-47.7 2 11.07 32 0.71 4.96 702 0.61 7.94 46-47.7 311.07 18 1.72 4.00 702.3 0.42 2.55 46-47.7

Example 9 Analysis of Food Remains Content

Food analysis was performed on an SUW sample and on an extrudateprepared from the same SUW following to the preparation procedureprovided for extrudate II. The analysis was performed according to thefood analysis guidelines provided by the Association of AnalyticalCommunities. The results are summarized in Table 13.

TABLE 13 Mechanical properties of injection molded samples of thecomposite material having different volatile liquids content TestedResult for raw material Result for Yuvalite parameter (%) (%)Carbohydrates 63.9 51.0 Protein 2.9 2.2 lipids 1.5 1.4 Starch <0.05<0.05 Soluble fibers 0.2 0.1 Soluble sugars <0.05 <0.05

Example 10 Designed Articles

Reference is now made to FIG. 13A-13E providing pictures of variousshaped articles which were made by using the composite material of theinvention. The composite material was prepared by making an extrudatefollowing the procedure that was described for extrudate II using theErema extruder and an extrusion temperature of 190° C. The extrudate wasgranulated and sieved to obtain granules having a maximal size of 0.7mm. The granules were reintroduced to the home made extruder at aworking temperature of 160-170° C. The new extrudate was granulated andsieved to obtain granules having sizes as customary in the plasticindustry. The resultant composite material granules were used plainly ormixed with various materials to produce articles with a designed shape.For example:

-   -   1. FIG. 13A shows a top view of a 18 Kg Pallet designed for        storage and moving by forklifts was prepared by injection        molding a mixture comprising a composite material granules/HDPE        2.5, 60:40 w/w %, on a 1700 ton locking force machine.    -   2. A tool box (not shown) was prepared by injection molding a        composite material granules/copolymer of PP (high flow) 2.5,        50:50 w/w % mixture at 220° C., on an 800 ton locking force        machine.    -   3. A shelf for installing in a cupboard (not shown) was prepared        by injection molding of a composite material granules/homo        PP/calcium carbonate concentrate 60:33:7 w/w % mixture at        215° C. on a 500 t locking force machine.    -   4. FIG. 13B shows a residential composter bottom part made of        the composite material of the invention. The bottom of the        composter as well as other parts that are not shown were        produced by injection molding of a composite material        granules/copolymer PP/carbon black concentrate 70:28:2 w/w %        mixture. at 190° C.    -   5. Sewer opening cover (FIG. 13C) was produced by injection        molding of 100% composite material granules at 210° C. on a 120        t machine    -   6. Sewer manhole base (not shown) was made by rotational molding        of a composite material granules/HDPE 2.5 60:40 w/w % mixture.    -   7. FIG. 13D shows flower pots that were made by cold compression        molding of 100% composite material extrudate on a 250 ton press.        The flower pots where painted using various types of paints such        as plastic, water based and oil paints.    -   8. A tubular body (FIG. 13E) with rectangular cross-section that        was made by extrusion at 200° C. of a composite material        granules/copolymer PP (low flow) 50:50 w/w % mixture.

Example 11 Adhesion of Moldings Made of the Composite Material

The adhesion properties of the composite material of the invention wereutilized for preparation of articles made from several moldings of thecomposite material that were adhered to each other using epoxy glue.Molded layers of the composite material were also adhered to other typesof materials. The following is a non-limiting example:

A countertop comprising a base and a working surface on top of the basewas prepared by adhering a plate made of the composite material servingas the base to a pseudo-marble stone serving as the working surfaceusing colored plaster as the adhesive. The molded plate was prepared bycompression molding according to the procedure described in Example 10(using 220 ton pressure)

Example 12 Pilot Plant Design

Reference is now made to FIG. 14 showing a schematic illustration of asystem 100 for processing SUW according to one embodiment of theinvention.

As shown, SUW is a priori collected in a tipping floor 110 from whichthe SUW is conveyed, via a dedicated feeding conveyer 112 a to twosequential shredders 114, where the SUW is particulated into particlesin the size range of centimeters, typically 8-10 cm. While the systemincludes according to this embodiment two sequential shredders, it maysimilarly comprise a single shredder as well as more than two shredders,ordered sequentially or in parallel. The shredders 114 may be any ofthose commercially available, such as the single shaft rotary shredderof Zerma (ZERMA Machinery & Recycling Technology (Shanghai) Co., Ltd.).

The shredded particles are then conveyed via a feeding conveyer 112 b totwo parallel granulators 116, to form particulate matter with a size ofseveral to tens of millimeters, e.g. 2-20 mm. Two granulators are shownin parallel. The parallel setup of the granulators is needed to equalizethe shredder outputs that are typically much higher than those ofgranulators.

It is noted that the shredded material does not necessary need to befurther reduced in size and that the system may be similarly operatedwithout the granulator. Further, while the present embodimentillustrates two granulators, positioned in parallel, the system maysimilarly be operated with a single granulator, as well as with morethan two granulators, the granulators being in parallel or in sequence.

The size reduction of the waste may take place in two stages, the firstbefore drying the waste, and the second after drying with a stream ofhot air. During the size reducing stages (shredding and grinding),liquid expelled from the SUW is collected via a liquid removal subunitcomprised of dedicated pipes 118, into a liquid collection unit 120. Theliquid may be removed by pressing the matter.

The particulate matter exiting the granulator 116 (or the shredder 114,in case there is no granulator) is then conveyed via conveyer 112 c intoa drying unit 122. Conveyer 112 c may be a magnet conveyer such as thatmanufactured by Zerma so as to remove metals (e.g. ferrous metals) fromthe particulated matter, prior to drying. The drying unit 122 may be adrum dryer as known in the art. The particulate matter is at leastpartially dried, but preferably not to completion (i.e. some amount ofwater needs to be retained in the particulate waste).

The partially dried particulate matter may then be supplemented withadditives via a feeding tank 124 being connected to the upstream end ofan extruder 126. Feeding of additives and other compensating substancesdepends on the desired characteristics of the product. For example, thedried particulated matter may be supplemented with wood chips.

Extruder 126 may be any extruder known in the art capable of mixingwhile heating the matter being mixed therein and expelled therefrom. Inthis particular embodiment, the extruder is a single screw extruder. Theextruder 126 is set to heat the matter therein to a temperature betweenabout 100° C.-240° C., and even between about 180° C.-230° C., whereby aflowable material is formed and extruded from the downstream end of theextruder through melt distributors into dedicated production lines 128which may include a compression molding device (not shown), materialspray device (not shown), granulating device etc. Heating is preferably,although not exclusively, accomplished by electrical heating provided bythe extruder.

While the above describes one embodiment of a SUW treatment system forobtaining a thermoplastic like composite material according to theinvention, it is to be understood that many changes may be made thereinwithout departing from the spirit of the invention.

What is claimed is:
 1. A method of processing waste material,comprising: providing dried particulates comprising substantiallyunsorted dried municipal waste material, wherein the substantiallyunsorted dried municipal waste material consists essentially of 1 to 50wt % inorganic matter based on a total weight of the dried unsortedmunicipal waste material, 10 to 40 wt % plastic matter based on thetotal weight of the dried unsorted municipal waste material, and aremainder of non-plastic organic matter; and extruding the driedparticulates at a temperature of 150 degrees Celsius to 210 degreesCelsius under sufficient shear forces to thereby obtain a compositematerial; wherein the composite material has a notched izod impact above12 J/m, has a surface energy of at least 40 dyne/cm, and wherein asample thereof that has been subjected to injection molding, hasthermoplastic properties with at least two of the following: tensilestrength of above about 2.7 MPa, tensile modulus of above about 600 MPa,flexural modulus above about 690 MPa, flexural strength above about 5.6MPa, and Charpy Impact above about 1.5 KJ/m².
 2. The method of claim 1,wherein the temperature is 150° C. to 180° C.
 3. A method of processingmunicipal waste material, comprising: providing dried particulatescomprising substantially unsorted dried municipal waste material,wherein the substantially unsorted dried municipal waste materialconsists essentially of 1 to 50 wt % inorganic matter based on a totalweight of the dried unsorted municipal waste material, 10 to 40 wt %plastic matter based on the total weight of the dried unsorted municipalwaste material, and a remainder of non-plastic organic matter consistingessentially of cellulose, hemicellulose, lignin and combinationsthereof; and extruding the dried particulates at a temperature of 150degrees Celsius to 210 degrees Celsius under sufficient shear forces tothereby obtain a composite material; wherein the composite material hasa notched izod impact above 12 J/m, has a surface energy of at least 40dyne/cm, and wherein a sample thereof that has been subjected toinjection molding, has thermoplastic properties with at least two of thefollowing: tensile strength of above about 2.7 MPa, tensile modulus ofabove about 600 MPa, flexural modulus above about 690 MPa, flexuralstrength above about 5.6 MPa, and Charpy Impact above about 1.5 KJ/m².4. The method of claim 3, wherein the temperature is 150° C. to 180° C.5. A method of processing waste material, comprising: extrudingparticulate dried material consisting essentially of substantiallyunsorted dried municipal waste material at a temperature of 150 degreesCelsius to 210 degrees Celsius under shear forces to thereby obtain acomposite material; said dried material consisting essentially of 1 to50 wt % inorganic matter based on a total weight of said dried material,10 to 40 wt % plastic matter based on a total weight of said driedmaterial, and a remainder of non-plastic organic matter; wherein thecomposite material has a notched izod impact above 12 J/m, has a surfaceenergy of at least 40 dyne/cm, and wherein a sample thereof that hasbeen subjected to injection molding, has thermoplastic properties withat least two of the following: tensile strength of above about 2.7 MPa,tensile modulus of above about 600 MPa, flexural modulus above about 690MPa, flexural strength above about 5.6 MPa, and Charpy Impact aboveabout 1.5 KJ/m².
 6. The method of claim 5, wherein the temperature is150° C. to 180° C.
 7. The method of claim 5, wherein the non-plasticorganic matter consists essentially of cellulose, hemicellulose, ligninand combinations thereof.